HARVARD UNIVERSITY 
LIBRARY 
OF THE 
GRAY HERBARIUM 
Received 
\H ^ 





ARNOLD ARBORETUM 
HARVARD UNIVERSITY 
ARNOLDIA 
A continuation of the 
Bulletin of Popular Information 
VOLUME III 
x 943 
PUBLISHED BY THE 
ARNOLD ARBORETUM 
JAMAICA PLAIN, MASSACHUSETTS 

Digitized by the Internet Archive 
in 2017 with funding from 
BHL-SIL-FEDLINK 
https://archive.org/details/arnoldiaarno_1 

ILLUSTRATIONS 
Hardiness Map. Plate I, p. 58. 
Needle of hemlock (a) with petiole and spruce (b) without petiole. Figure 1, 
p. 58. 
(a) Tsuga canadensis, (b) Tsuga Siebo/dii. (c) Tsuga caroliniana. Figure 2, p. 58. 
Tip of one year shoot of Picea pungens showing a majority of the needles nearly 
at right angles to the twig. Figure 3, p. 60. 
End bud and base of one year shoot of Picea po/ita (a) and Picea Abies (b) show- 
ing the tight fitting scales on bud and shoot base of P. polita as compared 
with those of P. Abies. Figure 4, p. 60. 
Tip of one year shoot of Picea Enge/rnanni showing a majority of the needles at 
less than right angles to the twig. Figure 5, p. 61. 
Cross section of needle of Picea Omorika and Picea glauca. Figure 6, p. 6 '--2. 
Side view of shoot of Picea obovata and Picea glauca showing the difference in the 
way the needles are borne on the twig. Figure 7, p. 64. 
(a) Twig of fir showing the smooth twig surface when the leaves have fallen (b) 
Twig of spruce showing the small leaf bases (making a rough twig surface) 
which remain after the leaves have fallen. Figure 8, p. 66. 
(a) Terminal bud of fir. (b) Terminal bud of Pseudotsuga iaxifolia showing its 
many scales and long pointed character distinctly different from the buds of 
any fir. Figure 9, p. 66. 
(a) Abies koreana. (b) Abies alba, (c) Abies Nordmanniana. Figure 10, p. 67. 
(a) Abies holophylla. (b) A. jirma. (c) A. cepha/onica. (d, e, f) Rounded and 
slightly notched needles commonly found on most firs. Figure 11, 68. 
(a) Needles mostly at right angles to twigs as in A. homo/epis, also showing long- 
; itudinal lines or grooves in twig, (b) Needles mostly directed towards the tip 
of twigs as in A. Nordmanniana. Figure 12, 69. 
[Hi] 


ARNOLDIA 
A continuation of the 
Bulletin of Popular Information 
of the Arnold Arboretum, Harvard University 
Volume 3 
MARCH 26, 1943 
Number 1 
PLANTING VEGETABLES 
HIS spring everyone will be interested in aiding the war effort by growing 
JL vegetables. Much is being published in the popular garden magazines about 
what to plant and when to plant it, as well as by our colleges of agriculture, hor- 
ticultural societies, and other organizations, 'the Arnold Arboretum can contribute 
little to this concerted effort but it is believed that the tabulated data included 
in this paper will prove to be of value at least to the amateur growers. A careful 
examination of this table will show that it includes practically all of the necessary 
information, answering the questions of how much to plant, how far apart to 
plant, when to plant, and when and how much of a crop to expect. 
Varietal names of vegetables purposely are not given, for at the time this table 
was prepared there was such a demand for vegetable seeds that many of the seed 
houses were completely sold out of the better varieties. Demands for seeds are 
three months ahead of schedule. The longer the choice of varieties is delayed, 
the fewer there will be from which to choose. Many agricultural experiment sta- 
tion and extension service publications are available in the different states wherein 
the better varieties are listed, and these might be consulted if time permits. 
An interesting innovation suggested here is a planting schedule worked out on 
the basis of the time that certain flowering trees and shrubs are in full flower. In 
every planting table seen to date, the exact dates of planting are given with the 
note that allowances must be made for variations in the current season. This al- 
ways is indefinite. Why not watch some plant growing in the open in a situation 
comparable to that of the vegetable garden? When this plant is in full bloom, 
or the leaves are appearing — then would be the time to sow certain seeds. The 
idea, of course, is that the climate governs the blooming periods, hence the sug- 
gestion of correlating the time of planting certain vegetable seeds with the time 
of flowering of certain characteristic native and introduced plants. The old Indian 
custom was to wait for sowing corn until the leaves on the oaks were the size of 
a squirrel’s ear. 

In any event, the sowing of seeds in accordance with nature's time table sounds 
feasible, and the plant groupings below are offered as illustrating planting dates 
in the vicinity of Boston. There is no reason why the correlation cannot be made 
for other regions, even outside of New England. 
APPROXIMATE PLANTING DATES 
The plants in each group start to bloom about the same time. It is suggested 
that such plants, if grown in unprotected places, be watched as indicators 
for planting the different kinds of vegetable seeds. (See Chart pp. 4-5). 
I (April 10-20) 
Forsythia intermedia 
Forsythia suspensa 
Epigaea repens 
Chionodoxa Lucilliae 
Lind era benzoin 
Scillas 
Salix babylonica - leaves appearing and 
then turning green 
II (April 25-May 5) 
Alyssum saxatile 
Amelanchier canadensis 
Amelanchier laevis 
Acer platanoides 
Chaenomeles lagenaria 
Daphne cneorum 
Dicentra spectabilis 
Iberis semper virens 
Magnolia stellata 
Magnolia Soulangeana 
Muscari botryoides 
Narcissus Poeticus 
Narcissus Barri 
Phlox subulata 
Primula polvantha 
Primus Sargentii 
Prunus subhirtella 
Vaccinium angustifolium laevifolium 
Vaccinium corymbosum 
III (May 15) 
Bearded Iris 
Berberis Thunbergii 
Berberis vulgaris 
Cercis canadensis 
Cornu s florid a 
Darwin Tulips 
Malus arnoldiana 
Malus floribunda 
Malus pumila 
Malus purpurea 
Paeonia suffruticosa 
Prunus persica 
Syringa vulgaris 
Trollius europaeus 
IV (May 25) 
Linum perenne 
Lonicera Morrowii 
Lonicera tatarica 
Malus ioensis plena 
Rhododendron nudiflorum 
Rosa Hugonis 
Spiraea Van Houttei 
Viburnum tomentosum plicatum 
Wisteria sinensis 
V (June 3-5) 
Crataegus phaenopyrum 
Iris sibirica 
Kolkwitzia amabilis 
Laburnum vulgare 
Paeonia officinalis 
Rhododendron calendulaceum 
Robinia pseudoacacia 
Rosa Harisonii 
Rosa multiflora 
Rosa rugosa 
Sorbus aucuparia 
Viburnum opulus 

PESTS IN THE VEGETABLE GARDEN 
There are many insects and diseases that infest growing vegetables, but only 
a few are prevalent to any great extent in New England. The following pests are 
common, and possibly will be encountered in most vegetable gardens this sum- 
mer. Recommendations for the control of these pests are given by all the state 
agricultural experiment stations, and are merely repeated here for the sake of 
convenience and as a part of the Arnold Arboretum’s contribution to the Victory 
Garden program. The most effective control is one which is applied early, before 
the pests become firmly established. Watch for the pests and apply the dust or 
spray promptly as soon as they appear. 
Cutworms: These are sometimes present in very large quantities and are most 
troublesome between the middle of May and the middle of June. They feed at 
night upon newly planted cabbage, eggplant and tomato plants, in addition to 
many others, cutting the plants off' just above the soil level. During the day they 
hide under stones or in the upper half inch of soil and many can be easily dug 
up by merely scratching the soil surface. The type which has been particularly 
injurious around Boston during the past few years is the dingy cutworm. 
One method of preventing injury to young plants is to provide them with a 
collar of stiff' paper, placed completely around the stem for one inch below and 
one inch (or more) above the soil level. Six thicknesses of newspaper would suf- 
fice. This collar prevents the cutworms from getting at the succulent young stems. 
Sometimes a garden may be severely infested, for the number of cutworms are 
governed from year to year chiefly by the amount of rainfall the previous year. 
Much rain forces them to the surface where birds and predatory insects eat them 
or else the excess moisture prevents the females from laying eggs in satisfactory 
places. A satisfactory bait which aids in the control of these pests is as follows : 
1^ lbs. bran 
1 o/. paris green 
1 cupful of molasses 
juice of one orange or lemon 
l^- c 2 quarts of water, mix thoroughly 
This should be applied, at the rate of lbs. per quarter acre, along the rows 
of vegetables during late May and June when injury is worst. Since the cutworms 
feed chiefly at night, the fresh bait is best distributed just before sunset. It should 
be noted that this poisonous bait may be fatal to dogs, cats, and other pets. It 
i should be used with discretion. 
Cabbage maggots: These often infest the roots of early planted cabbage and 
| cauliflower plants in June, causing the young plants to wilt and die quickly. In- 
jury to the plants can be prevented if a square or circular piece of heavy paper 
about 3-4 inches in diameter is placed on top of the soil at the base of the plant. 
To fit snugly, the paper is slit and a small hole cut at the center, barely large 

PLANTING INFORMATION 
When 
mature 
jfjijnjmi oj s^99^ 
6-9 
10-13 
CO 
13-17 
T- 
i 
GO 
1 
00 
13-17 
13-17 
00 
When 
to 
plant 
juujd oj 9mij j 
> 
> 
- 
- 
- 
“ 
- 
How to plant 
sXup ui pouod uox^uniuu9Q 
00 
1 
■4 
4-8 
o 
t- 
Tp 
5-10 
WO 
CM 
00 
CO 
S9q9Ul UI p99S JO qjd9Q 
- 
- 
t— r|c<i 
th|n 
H<n 
iHj(N 
sjuiqd u99Avj9q soqouj 
1 
<M 
<M 
00 
C 
CM 
CM 
o 
CM 
6-8 
o 
CM 
savoj u99AVj9q soqouj 
o 
GO 
O 
GO 
CM 
CO 
GO 
O 
GO 
CM 
O 
GO 
o 
co 
CM 
How mueh seed 
J99j ui sjuujd 9ouno \ 
o 
o 
O 
W0 
1 
1 
O 
O 
CM 
1 
I 
100 
avoj jo J99j ui sjuiqd ’jqd x 
«0 
CM 
o 
CM 
^0 
CM 
250 pits 
250 pits 
O 
GO 
150 pits 
400 pits 
wo 
CM 
a\o.i jo ,001 poos *juiy 
M 
o 
CM 
N 
O 
CM 
X 
0 
<M 
1 pkt 
1 pkt 
N 
O 
Hcq 
-M 
0- 
1 pkt 
1 oz 
How much 
produce to 
plan for 
spunod ui avoj jo qj^uoj 
siqj uiojj p9j99dx9 ppiy 
o 
GO 
W0 
O 
<M 
o 
CM 
o 
O 
CO 
wo 
30 pits. 
wo 
JU9^ l JOJ 
uosjod x Joj avoj qjSuoq 
WO 
t- 
W0 
CM 
o 
GO 
O 
CM 
o 
CM 
o 
WO 
wo 
Beans bush (snap) 
Beans bush (lima) 
Beets 
Broccoli 
Cabbage 
Carrots 
Cauliflower 
Celery 
Chard 

1 
GG 
GC 
so 
C- 
i 
GO 
GO 
13-17 
t- 
i 
1 
0^ 
oc 
1 
L— 
GO 
t- 
o 
1 
00 
CX 
0-1 
1 
00 
<x 
1 
t— 
7 
1 
> 
5 
" 
- 
- 
- 
> 
1 a 
- 
> 
- 
a 
> 
- 
- 
o 
oc 
4 
CO 
CO 
00 
cx 
*o 
CO 
i 
t 
00 
oc 
*o 
CO 
CO 
00 
1 
tJi 
- 
H<N 
i— l|<N 
r+tf 
i— i|c<i H<x 
Hcq 
Hn 
cx 
- 
H<n 
<X 
00 
CX 
ex 
7 b 
i 
GO 
G^ 
o 
CX 
<X 
«o 
I ex 
-f* 
<x 
cx 
7 b 
-sf 
(X 
Tf< 
ex 
O 
00 
o 
cx 
‘O 
CX 
ex 
O 
GO 
§ 
§ 
ex 
o 
CO 
ex 
© 
i 
CO 
o 
CO 
1 
■1 
1 
1 
o 
o 
CX 
1 
° i 
° 
CX 1 
o 
o 
<X 
o 
o 
ex 
r- 
1 
1 
»o 
r~ 
° 
o 
o 
1 
1 
G^ 
73 
c 
1 
1 
X 
*o 
03 
+-> 
'a 
o 
o 
o 
GO 
X 
*0 
o 
*o 
>o. 1 
<X 42 
o 
o 
cx 
o 
X 
-M 
1 
o 
CX 
*o 
ex 
iO 
G^ 
X 
03 
-4-> 
o 
o 
<x 
o 
»o 
4-i 
-M 1 
S3 
H<n 
-M 
N ■+-> 
tH|<M 
N 
s 
° 
s 
-M 
Ho 3 ' 
s 
o 
Hca 
N 
ex 
N 
0 
N 
O 
-M 
X 
-M 
K/ 
n 
G^ 
1 110 ears 
GO 
03 
03 
o y 
CX 
o 
O 
o 
CO 
i- 
O 
(X 
03 
y 
00 
o 
ex 
MO 
CO 
o 
cx 
140 
4 
hills 
uo 1 
1 
W3 
o 
cx 
o 
CX 
*-3 
1 
o ! 
ex 
2 
o 
«o 
ex 
U0 
o 
Tft 
o 
X 
^ 3 
ro «5 
CO 
o 
cx 
Corn 
03 
S-, 
y 
42 
y 
6 
b£ 
b£ 
w 
<U 
y 
3 
-M 
y 
h-1 
03 
0 
'y 
S 
XI 
1 
li) -M 
OJ OJ 
Cfl XI 
X 
w 
4J 
X 
X 
X 
a 
03 
3 
y 
03 
U 
y 
y 
X 
<U 
o 
-M 
03 
y 
73 
23 
03 
y 
,p 
o 
m 
y 
m 
03 
2 
in 
03 
y 
o 
4-> 
H 
X 
H 

enough for the stem of the young plant. The outside edges of the paper are held 
down with soil. This prevents the fly from laying the eggs in soil cracks at the 
base of the plants. 
Cabbage worms: These are the small worms which infest the heads of cab- 
bage, broccoli, cauliflower and other related plants. They appear from June to 
September. Lead arsenate spray or dust can be applied until the heads are one- 
third grown, then pyrethrum dust can be used. If pyrethrum dust is available in 
sufficient quantity, it might be substituted for the lead arsenate, since lead arsen- 
ate is poisonous to human beings and should not be used if at all possible. Roten- 
one dust is very effective also, but as this may be difficult to obtain later in the 
season it should be conserved as much as possible. It may be necessary to make 
two or three applications, preferably while the worms are still small. 
Mexican bean beetles: These are the coppery colored lady bugs’’ appearing 
on snap beans and lima beans from July to September. In many gardens they 
are very numerous and steps must be taken for their control as soon as they ap- 
pear. The eggs are yellow and are laid on the under surface of the leaves; the 
spiny, yellowish larvae do most of the damage for they eat holes in the leaves 
causing the leaves to resemble lacework. 
Rotenone or pyrethrum dust are both effective in controlling these insects. 
(Lead arsenate would be effective except that it should not be used because of its 
poisonous effect on human beings.) The dust should be applied to the under sur- 
face of the leaves where the larvae feed. The larvae and insects must be thoroughly 
covered with the insecticide, and thus it may take two treatments at an interval 
of three days to control the infestation. There are small dusters on the market! 
which are admirably suited for directing the dust to the under surface of the leaves. 
Because the mature insects live over winter in old rubbish, it is advisable to pull 
up and burn all bean plants as soon as the crop has been harvested. 
Since rotenone is so effective in the control of the Mexican bean beetle, it is 
fortunate that the War Production Board still allows its use for this purpose. 
Rotenone is deadly to insects but not injurious to human beings. Its supply is 
becoming increasingly limited and an order of the War Production Board (ordei! 
no. 138 as amended Jan. 23, 1943) restricts its use to the following: — peas (pro- 
tection against pea weevil and pea aphid); beans (protection against the Mexican 
bean beetle); cole crops — other than cabbage — including: broccoli, brussels 
sprouts, cauliflower, kohl-rabi, mustard, kale, turnips and collards (protection 
against caterpillars and aphids); sweet corn (protection against the European 
corn borer). 
Striped cucumber beetles: These beetles are destructive of melons, squash anc 
cucumber plants. They are the most severe pests of cucurbits east of the Rocky 
Mountains, for they not only feed on the leaves of the plants, but they carry a 
serious bacterial wilt from one plant to another. They are familiar to every gar 
dener for their black and yellow striped bodies cannot be mistaken. It is ven 

important that they be controlled, for if these be eliminated, this will control the 
pread of bacterial wilt. 
The use of rotenone is not permitted on cucurbits, and so the next best con- 
rol method is to use a dust consisting of ten parts calcium arsenate and ninety 
>arts talc. Treatments should be thorough on all plants, and should be repeated 
t weekly intervals from the time the beetles first appear, which frequently may 
,>e when the young plants have from four to six leaves. 
Squash vine borers: These borers eat their way into the base of the stems or 
unners of squash plants causing them to wilt and die before the fruit reaches 
maturity. It is possible, in small gardens, to watch for these pests and remove 
hem with a knife. Then by covering up the cut portion with moist earth, the 
tern may continue growth. Since rotenone is unavailable for use on cucurbits, 
jyrethrum might be used, dusting four times at seven day intervals, the first 
reatment being given by the end of June. Other sprays recommended are (l) 
licotine sulphate, one part in one hundred parts of water with one-half part fish 
>il soap for a sticker; (2) three pounds of lead arsenate and one quart of fish oil 
.oap in one hundred gallons of water; (3) Bordeaux mixture to which is added 
ome lead arsenate or calcium arsenate. This should be applied three or four times 
t weekly intervals. It is very difficult to reach the borers since they feed on the 
fiside of the stems, but sometimes these sprays prove to be effective for killing 
he young insects before they enter the stems. 
Potato bugs and potato blight: These common pests are undoubtedly familiar 
o everyone. Potato growers usually spray from two to six times with Bordeaux 
nixture to control the blight and other potato diseases. The first spray is applied 
^hen the plants are six to eight inches high and other applications follow at in- 
tervals of from ten to fourteen days. Earlier applications would be at 4-4-50 
trength (hydrated lime — copper sulphate — water)and later applications at 6-6-50. 
)ry Bordeaux is purchasable from most seed stores, and so the gardener with a 
mall vegetable garden is not confronted with the difficulties of making his own 
Bordeaux mixture. In using Bordeaux mixture, lead arsenate might well be added 
\ hen applications are made during late spring and early summer for the control 
»f the potato bug. Or, lead arsenate can be used alone to control the potato 
>eetle, using one pound of lead arsenate to fifteen gallons of water. 
Of course there are many other insect and disease pests, often occurring in some 
ections but absent in others. The few mentioned here are the most prevalent 
•lies. If these are not kept in check, the returns from some of the crops will be 
j ery disappointing indeed. If they are kept in check, many gardeners can reason- 
ably expect full returns on the time and money they have invested in their gardens. 
Donald Wyman 
[ 7 ] 

“SYLVA TELLURIANA” OF RAFINESQUE 
Last year we announced the facsimile lithoprint reproduction of the very rare 
“Autikon Botanikon” of Rafinesque, pp. 1-200, originally published in Philadel- 
phia in 1840 in a limited edition. We now announce a similar facsimile lithoprint 
edition of the equally rare “Sylva Telluriana” of Rafinesque, pp. 1-184, published 
originally in Philadelphia in 1838. These two very rare botanical volumes have 
long been entirely unavailable to botanical and other libraries, only about a dozen 
copies of each being known to be in existence. These modern facsimile editions 
are much easier to consult than are the originals, as both of Rafinesque’s books 
were printed on poor paper which is now badly discolored. These volumes may 
now be had from the Arnold Arboretum, the “Autikon Botanikon” reprint being 
priced at $3.00 and the “Sylva Telluriana” at $*2.50. If the demand for these 
is reasonably good, it is probable that the larger and equally rare “Flora Telluri- 
ana” of Rafinesque, four volumes, Philadelphia, 1836-38, will be similarly repro- 
duced. This reproduction service is of great importance to the libraries of technical 
and educational institutions, as copies of the originals cannot be purchased at 
any price. 
JAMES B. CASE MEMORIAL 
The Arnold Arboretum of Harvard University has recently received an outright 
gift of $50,000.00 from Miss Louisa W. Case of Weston, Mass., together with 
her residence, barns, greenhouses, and fifty-nine acres of land in Weston, to be 
utilized for the general purposes of the Arboretum. The real estate is assessed at 
$84,000.00, Miss Case’s gift thus being in the neighborhood of $134,000.00. 
The gift is a memorial to her father, James B. Case. Several hundred hybrid 
crabapples and cherries have already been planted by the Arboretum staff on the 
Case estate. 
[ 8 ] 

ARNOLDIA 
A continuation of the 
Bulletin of Popular Information 
of the Arnold Arboretum, Harvard University 
glume 3 APRIL 16, 1943 Number 2 
THE NAMING OF HORTICULTURAL VARIETIES 
V/fANY an intelligent plantsman is up against a blank wall when it comes to 
A A providing a name for some new plant he thinks he has found. Shall the 
ame be in Latin or in English? Shall it be a botanical variety, a horticultural 
ariety, or a 4 ‘form”? If it is a hybrid, just what is the correct procedure in order 
p give it a proper name that will be accepted by horticulturists and botanists 
like? There is an ever-increasing tie between the botanist and the practical 
lantsman, as far as the scientific names of plants are concerned, for both groups 
ave agreed that it is best to follow the International Rules of Botanical Nomen- 
lature, as approved by the International Botanical Congress, Cambridge, Eng- 
md, 1930. 
Even though everyone agrees to the International Rules, the naming of new 
lants is difficult, and in the following discussion it is hoped that the correct 
rocedure for naming new varieties is clearlv set forth. 1 
Variety 
First, it is necessary to understand the concept of a botanical variety. The cor- 
?ct definition would be — A variety is a subdivision of a species composed of 
idividuals differing from other representatives of the species in certain minor 
liaracters which are often of geographical significance, and which are usually 
erpetuated through succeeding generations by seed. 
Form 
A form is a subdivision of a species or variety , usually differing in only one char- 
ter and often appearing sporadically throughout the range of the species ; it is 
sually perpetuated vegeta tively but may be perpetuated by seed, in which case 
luly a certain percentage, as a rule, will be identical with the original form and 
ie remainder will revert to the species or variety. 
In some cases no clear line between a variety and a form can be drawn. Also, 
1 .See also Jour. Arnold Arb. 10: 65. 1929. 

the two terms have been used and are used interchangeably, so that differentia- 
tion between the two is often exceedingly difficult. Both the variety and the form 
as above described should be given a Latin name, and the original published de- 
scription should include a short Latin description. The form or the variety may 
occur again in nature, and if it conforms to the original description, it would be 
given the same name no matter where or when it occurs. 
Cion 
On the other hand, there is a large group of plants which fail to come true 
from seed. Individuals in this group may be outstanding, and are perpetuated 
solely by asexual propagation of one kind or another. Such plants may be con- 
sidered forms or they may be considered cions (formerly spelled clones). A clou 
is a group of plants composed of individuals reproduced vegetatively from a single 
plant. Hence, though a form may also be propagated vegetatively (a cion must 
be), the form may appear again anywhere at anytime and should be given the 
same name as its predecessor, whereas the cion constitutes a group of plants 
propagated from a single specimen , and if all the members of this group should 
happen to die, no plant in the same genus should ever be given the same name 
again regardless of where or when it occurs. 
If the plant is considered a form, it is given a Latin name, and any time in the 
future that a plant is found conforming to the original description, it takes the 
same Latin name. In other words, a form name is one given to a group of indi- 
viduals which may have originated over widely separated areas. A cion name is 
one given to a single individual and its vegetatively propagated progeny. 
If considered a cion, the plant is given a vernacular name — a noun or an ad- 
jective used as a noun, in any language, as 4 4 Transcendent,” 4 4 Snow White,” 
“l)olgo,” or “Wabiskaw.” Any plant with such a name must be propagated 
asexually in a direct line from the one original plant. 
Selecting the New Name 
It is evident from the above descriptions of terms that giving Latin name> 
(species, varieties, forms) to plants should be done by individuals who are trained 
taxonomists. In the past many plantsmen have tried to give Latin names to so- 
called “new” individuals, but because they did not know the entire group thor 
oughly nor the literature on the subject, such names, in many instances, havt 
been proved worthless and unfortunately continue to clutter up many a nursery 
catalogue. 
Consequently, the amateur should give a horticultural varietal name in English 
unless he is certain he has a new species, variety or form, in which case he should, 
get confirmation of his Latin name and Latin description from a trained taxono 
mist who is in a position to know the literature pertaining to the plant group ir 
question. 
If a certain plant is given a varietal name in English, it will always designah 
that particular cion even though some taxonomist at some future date may, ir 
[ 10 ] 

working over several similar cions, mention their similarity and give a Latin name 
(variety or form) to the group. This is possible and permissable, but the cion 
name still remains in use for that particular plant regardless. 
Horticultural varietal names in English (i.e., cion names) would be best for 
most new varieties of Malus appearing that may be worthy of naming. Such 
names should be simple and to the point whenever possible. “ Bob White” is a 
very good one. Mr. C. S. Sargent” or Prof. C. S. Sargent” are not. The name 
t might better be “Professor Sargent” or “Charles S. Sargent.” The same brevity 
is needed with the prefix ‘Mrs.” or “Miss.” It is far better to give the full 
name, as “Henrietta White” rather than “Mrs. White” or “Mrs. A. R. White,” 
or “Mrs. Alfred R. White.” Taking the last two instances as examples, such 
: names are easily confused in making labels and it is never long before such varie- 
ties become changed to “Mr. Alfred It. White” and finally to “Alfred It. White.” 
Rules for Selecting New Horticultural Variety Names 
The International Horticultural Conference in London (1930) adopted several 
| resolutions dealing with the naming of horticultural varieties. These have also 
5 appeared as an Appendix in the International Botanical Rules published in 1935. 
It behooves everyone who is interested in the naming of new horticultural varieties 
to study these resolutions and follow them in selecting new names for all plants. 
1. Names of horticultural varieties must not be translated when transferred from 
other languages, but must be preserved in the language in which they were orig- 
inally described. Where desirable a translation may be placed in brackets after 
the, varietal name. 
2. So far as possible, names of horticultural varieties should consist of a single 
word; the use of not more than three words is permitted as a maximum. 
3. A varietal name in use for one variety of a kind of plant should not be used 
for another variety of that kind, even though it may be attached to a different 
species. Thus the use of the name Narcissus pseudonarcissus “Victoria” should 
preclude the use of “Victoria” as a varietal name for any other species of Narcis- 
sus, such as Narcissus poeticus Victoria.” Similarly there should be but one 
Iris Bridesmaid,” one Plum Superb,” and so on. 
4. Varietal names likely to be confused with one another should be avoided. 
For instance, the use of the name “Alexander” should preclude the use of “Alex- 
andra,” “Alexandria,” and “Alexandrina” as varietal names for the same kind 
of plant. 
5. Where personal names are used to designate varieties, the prefix Mr., Mrs., 
Miss, and their equivalents should be avoided. 
(). Excessively long words and words difficult to pronounce should be avoided. 
7. The articles “a” and “the” and their equivalents should be avoided in all 
languages when they do not form an integral part of the substantive. For instance, 
Colonel,” not “The Colonel”; “Giant,” not “The Giant”; “Bride,” not 
“The Bride.” 

8. All the names of horticultural hybrids are formed as provided in the Inter- 
national Rules of Botanical Nomenclature. If a Latin name has been given to a 
hybrid form of uncertain origin which cannot be referred to a Latin binomial, it 
must be treated like a vernacular (fancy) name; e.g. , Rhododendron “Atrosan- 
guineum,” Rhododendron “Purpureum grandiflorum. ” 
Publishing the Name 
To be valid under the International Rules of Botanical Nomenclature, the Latin 
or scientific names of species, varieties, and forms must be “validly published” 
in a work accessible to botanists and the public in general, and a short description 
in Latin must accompany the original description. 
In publishing the names of horticultural varieties (cions), the Latin description 
is not required, but the description in English (or any other language written in 
Roman characters) should appear in a recognized horticultural or botanical period- 
ical, monograph or other dated scientific publication. The mention of a cion in a 
catalogue or in the report of an exhibition without a description is not considered 
valid publication even though a figure is given. 
Naming Hybrids 
From a botanical point of view, a cross may be designated by a formula con- 
sisting of the names of two plants joining to make the cross, i.e. Malm baccataX 
prun (folia. Whenever it seems useful or necessary” a name may be given to this 
cross, i.e., Mains robust a , in this case the name being given because the plant has 
considerable ornamental value, is grown a great deal, and the single name is more 
usable than the formula; it will include all the crosses however different between 
the two species, but the individual crosses, treated as cions, retain their horticul- 
tural names under it. 
It is correct (and always best for the amateur) to use the formula in speaking of 
a new cross, rather than to run into the difficulties of selecting a new Latin name. 
It is of the utmost importance to realize that hybrids are made up of cions which 
vary considerably in many characters. For instance, X Malus robusta is a hybrid 
(M. baccata pruni folia), the fruit and flower sizes varying considerably. In fact, 
some plants resulting from this cross are practically worthless ornamentally. So, 
when one merely buys XM. robusta, one may obtain anything within the limits 
of this cross, some decidedly inferior and some very good ornamentally. But, 
XM. robusta “Joan” is a cion with definite characteristics, and one is able to 
know in advance just what characteristics this particular cion will have. Conse- 
quently, horticultural varietal names should be given to the offspring of all crosses. 
Examples 
1 . A dogwood is found which has yellow fruits but in every other respect is 
identical with Cornus florida. Is it a variety, form or cion? Upon careful investi- 
gation it is found that yellow fruited dogwoods have appeared at widely separated 
places in the eastern United States. Hence, it is not a cion for it cannot have 
[ 12 ] 

been vegetatively propagated from a single specimen. It is not a variety for it 
differs from the species in only one character. Hence, it is a form, and it is given 
the name Cornus jior'ida xanthocarpa. 
2. A new crab apple has been found with unusually large double flowers. Noth- 
ing exactly like it has been described before, though some of its foliage characters 
are similar to those of M. Hal liana, and others similar to those of M. baccala. In- 
vestigation shows that a cross between these two species has been named M. 
Hartwigii, but on looking up the description of this cross, the new plant does not 
seem exactly to fit. Since it obviously is a hybrid it is also a cion, and the name 
“Katherine” is given it. At present it will be known merely as Malus “Kath- 
erine.” If at some future time fruits are available (they were not this year), it 
may be that this will definitely belong to the hybrid species XM. Hartwigii, and 
then it will be known as M. Hartxcigii “Katherine” or it still may be called M. 
“Katherine.” In any event, it will always keep the name “Katherine” regard- 
less of what hybrid species it is associated with, and all its offspring must be asex- 
ually propagated in a direct line from the one original plant now growing in 
Durand-Eastman Park in Rochester, New York. (It is always well to use quota- 
tion marks around all clonal names to differentiate them unmistakably from all 
other names.) 
Conclusion 
In naming new horticultural varieties it is essential to:^— 
1. Understand the differences betw r een a species, variety, form, and cion as 
here defined. 
2. Understand the rules for naming horticultural varieties as here set forth. 
8. Select the name. 
a. If a species, variety, or form, obtain confirmation from a trained taxono- 
mist regarding the name itself and the Latin description which must 
accompany its first publication, and which must conform to the Inter- 
national Rules of Botanical Nomenclature. 
b. If a cion or horticultural varietal name, be certain that it conforms to 
the rules set dowm in this paper. 
4. Publish the name and description. 
a. If a Latin name, publish (with Latin description) in some botanical 
periodical available to botanists and the general public as well. 
b. If a horticultural name, publish (without Latin description) in some ac- 
ceptable horticultural or botanical publication easily available to all. 
[ 13 ] 
Donald Wyman 

Notes 
Fruits still remaining' on shrubs and trees in the Arnold Arboretum on March 
26, 1943. Presumably the fruits of other plants have fallen. 
Aronia arbutifolia - dark brown, withered 
“ Brilliantissima ” - dark brown, withered 
macrophylla - 
“ melanocarpa elata - 
prunifolia - 
Berberis canadensis - a few bright red, still attractive 
“ koreana - dark red and withered 
“ ottawensis - few, bright red 
Thunbergii — bright red, still attractive 
argenteo-variegata - bright red, still attractive 
atro purpurea — dark red 
minor - bright red, still attractive 
verrueulosa pale blue, withered 
Celastrus orbiculata - orange red, withered 
seandens — 
Cotoneaster integerrima - few fruits, dark brown to black, withered 
obscura - 
Zabeli 
Crataegus Lavallei - dark brown, withered 
Ilex glabra - dull black, withered 
Ligustrum acuminatum — dull black 
acutissimum - 
amurense — 
ibolium — 
Ibota Tschonoskii — dull black 
obtusifolium - 
Regelianum — dull black 
vulgare — dull black and withered 
sempervirens — dull black and withered 
Malus Hartwigii — L lb°fo still on, remaining dark brown, withered 
micromalus - dark brown, withered 
Zumi 4 Bob White-' — .>0% still on, brown, withered 
calocarpa — dark brown, withered 
Phellodendron amurense — dull black, withered 
chinense — 
Lavallei - few remain, dull black, withered 
Bhodotypos seandens - dull reddish-black 
Kibes fasciculatum chinense — red orange, withered 
[n] 

Rosa alba - few remain, brown and withered 
“ arvensis - few remain, dark purplish red 
“ eanina inermis - reddish brown, still attractive 
“ eentifolia - few remain, brown and withered 
“ coriifolia - “ dark red, withered 
“ corymbifera - dark red, slightly withered 
“ Luciae - few remain, brown to black 
“ Maximo wicziana Jackii - glossy dark red 
“ micrantha - few remain, dark red, withered 
i i multiflora — glossy dark red, still attractive 
cathay ensis - glossy dark red, still attractive 
ii setigera - dark dull red, still attractive 
“ serena - dark dull red, still attractive 
“ virginiana - red to black, 7 o°/c are withered 
Symphoricarpos sp. - few remain but dark brown and withered 
Viburnum dilatatum - very dark red, withered 
lobophyllum - brown to red, withered 
Sargenti — a few withered fruits remain, red 
[ 15 ] 


ARNOLDIA 
A continuation of the 
Bulletin of Popular Information 
of the Arnold Arboretum, Harvard University 
Volume 3 MAY 14, 1943 Number 3 
WINTER FOLIAGE COLOR OF NARROW-LEAVED EVERGREENS 
L AST year a rather complete report was published on the foliage color of woody 
plants from April to September (Arnoldia 2: 57—68, 1942). Another bulle- 
tin on autumn color of deciduous plants (Bull. Pop. Information, Series 4, 4: 
83-90, 1936) covered that period in the fall when deciduous plants are most color- 
ful. This current issue of Arnoldia is devoted to the color of narrow-leaved ever- 
greens during the winter, and completes the study of foliage colors of woody plants 
throughout the year. 
This past winter has been an unusual one because temperatures dropped to 
-20° F. for very short periods on several occasions. This caused considerable 
winter injury to deciduous plants, and some to evergreens. There were no periods 
of continuous high winds so that little “burning” of evergreen foliage resulted 
from wind injury. Consequently, winter injury this year was due largely to low 
temperatures. A full report of injury to deciduous plants will be given at a later 
date when the amount of injury will be more evident than it is at present. 
Many evergreens change color in the fall and winter, some take on pleasing 
colors like Juniperus horizontalis plumosa , and others take on brownish tones which 
frequently make the plants look sickly or even as if they might be dying. Several 
varieties of Thuja occidentalis are in this category. The colors of evergreens noted 
in the following lists were maintained by the plants through the past winter until 
May 1, 1943, and might w r ell be compared with colors listed in the first reference 
above. 
NARROW LEAVED EVERGREENS 
Report on winter foliage color (Oct. 1942-April 1943) 
1. Gray (good foliage color) 
Chamaecvparis pisifera squarrosa 
squarrosa nana” 
Juniperus communis ‘O’Donnell” 
[ 17 ] 

Gray (good foliage color, cont.) 
Picea glauca 
mariana Doumetii 
4 4 purpurea 
2. Yellow (many plants with yellow foliage turn a dirty yellowish in the winter. 
Those mentioned below maintained their yellow color throughout last 
winter. 
Juniperus chinensis “japonica aureo-variegata” 
Thuja orientalis decussata 
3. Yellowish (very poor color for ornamental plants) 
Chamaecy paris obtusa 4 ‘gracilis a urea” 
pisifera “plumosa flavescens” 
Juniperus chinensis japonica 
“plumosa aurea” 
Smithii 
Taxus cuspidata aurescens 
Thuja occidentalis Ellwangeriana 
lutea 
4 4 4 4 “Waxen” 
4 4 4 4 Woodwardii 
orientalis conspicua 
elegantissima 
4-. Blue (good foliage color) 
Abies concolor 
Chamaecyparis pisifera squarrosa 
Juniperus horizontalis alpina 
scopulorum 
“Chandler’s Silver” 
glauca 
44 “ “Hill’s Silver” 
“Marshall’s Silver” 
44 “ “Medora” 
Moonlight” 
squamata Meyeri 
Virginia glauca 
Picea pungens Kosteriana 
Moerheimi 
5. Bluish green (good foliage color) 
Abies lasiocarpa 
Chamaecyparis pisifera minima 
[ 18 ] 

Bluish green (good foliage color, cont.) 
Juniperus chinensis mas 
Sargenti 
communis 
hibernica 
horizontalis 
Douglasii 
procumbens 
scopulorum “Cologreen” 
squamata 
Picea bicolor 
44 Glehnii 
pungens 
Pinus monticola 
44 parviflora 
sylvestris 
6. Purple (good foliage color) 
Juniperus horizontalis plumosa 
virginiana reptans 
7. Green (Plants maintaining their green foliage color throughout last winter. Of 
course the majority of narrow-leaved evergreens belong in this group but 
are not mentioned here because of lack of space. Because of the diver- 
sity of colors among the Junipers, individuals in this species which main- 
tained a good green color are mentioned here) 
Juniperus chinensis Pfitzeriana 
pyramidalis 
Watereri 
formosana 
glaucescens 
Sabina tamariscifolia 
scopulorum 4 4 Emerald” 
virginiana - however, this color may vary with different individuals, 
some being almost purple, some brownish 
Kosteri - one of the best for a normal green color through- 
out the winter 
i. Brownish (Plants not necessarily injured but the foliage of which normally turns 
brownish in the winter. A very poor color for ornamental plants) 
Chamaecyparis Lawsoniana 
obtusa compaeta 
pisifera aurea 
4 ‘plumosa argentea” 
[ 19 ] 

Brownish (plants not necessarily injured . . . , cont.) 
Juniperus communis depressa 
“depressa aurea” 
rigida 
Sabina 
virginiana - brownish green — some individuals, however, maintain 
a dark green foliage throughout the winter 
Sequoiadendron giganteum 
Taxus baccata aurea 
“ Dovastoni — 50% foliage killed 
“ erecta - injured by the winter 
“ lutea-50% foliage killed 
“ chinensis - 75% of foliage killed 
Thuja occidentalis ericoides “Rheingold” 
globosa 
orientalis 
Donald Wy 
MAN 
Note: At the time this is being written (May 8) there is comparatively little in 
bloom at the Arnold Arboretum. The early magnolias and shadblows are very 
much in evidence. The cherries, which are usually so noticeable at this time of 
year, have practically no flowers at all. Apparently the flower buds of many Primus 
species were killed by the cold of last winter. The crab apples, on the other hand, 
show promise of profuse bloom this spring, probably by the time this publication 
is in the mail. This is additional evidence in favor of planting more of the sturdy, 
dependable crab apples. The common Forsythia suspensa and F. intermedia varieties 
did not bloom. A few flowers appeared on F. ovata and F. europaea , and nearly 
fifty per cent of the flowers appeared on F. japonica saxatilis. Lonicera standishii , 
Cornus mas and C. officinalis, Lindera Benzoin , all bloomed as usual. Flower buds 
on Cory/opsis species, Rhododendron mucronulatum, Viburnum Jragrans and Pieris 
japonica were completely killed. 
[ 20 ] 

ARNOLDIA 
A continuation of the 
Bulletin of Popular Information 
of the Arnold Arboretum, Harvard University 
Volume 3 MAY 21, 1943 Number 4 
BROAD LEAVED EVERGREENS IN GOOD CONDITION WITH 
GREEN FOLIAGE THROUGHOUT THE WINTER 
(Oct. 1942 -April 1943) 
Arctostaphylos uva-ursi 
Buxus microphylla koreana - The only boxwood which was not injured 
["alluna vulgaris varieties - all in good condition but these were covered with ever- 
green boughs and snow during the coldest weather, 
"hamaedaphne calyculata - foliage bronze red 
Daphne Cneorum 
'Aionymus Fortunei colorata - foliage bronze red 
minima - foliage dark green to bronze red 
‘‘Silver Queen” - leaves variegated 
vegeta - in some locations plants have lost up to 30 % of leaves 
lex crenata 
convexa 
glabra 
‘ ‘ opaca 
“ pedunculosa 
' rugosa 
“ Sugeroki 
i 6 
yunnanensis 
almia Carolina 
latifolia 
I lahonia Wagneri - dark reddish purple 
achistima Canbyi - very dark purplish to green 
achysandra terminalis 
ieris floribunda 
I 4 6 
japonica 
f lotentilla tridentata - bronze red and dark green 
[ 21 ] 

Rhododendron species and varieties - the majority of the rhododendrons came 
through the winter with very little foliage injury — though the flower 
buds of many may have been killed 
Thymus sp. - green to reddish purple 
Vinca sp. and vars. 
BROAD LEAVED EVERGREENS WHICH HAVE BEEN INJURED 
DURING THE WINTER OF 1942-43 
Berberis candidula - all leaves remain on plant but they are brown and dead 
( ( i (( tt a <( n a a a a a a 
Chenaultn - 
a „ ... u a a a << “ (< << (( a << 
Gagnepainn 
triacanthophora “ “ “ , but a reddish brown 
verruculosa - ‘ ‘ “ , brown and dead 
Buxus sempervirens — all varieties of B. sempervirens had a considerable propor- 
tion of their leaves killed 
Cotoneaster Henryana — all leaves remain on plant but brown and dead 
microphylla - leaves dark brown, undoubtedly they will soon be dead 
Erica carnea - apparently 50% of plants have been killed 
Hedera Helix baltica — all leaves killed (plant was on a wall growing to a height 
of 50'). As a ground cover this might not have been s( 
severely injured 
Ilex crenata Helleri - dark green with slight burning 
Leucothoe Catesbaei - 75% of foliage injured 
Lonicera Henryi (growing on the ground) 50% leaves brown, rest green. Or 
trellis 50% of the leaves had fallen and the remainder were all deac 
Mahonia Aquifolium and vars. - reddish purple to brown, considerable injury 
Mahonia repens — reddish purple to brown, some winter injury 
Prunus Laurocerasus Zabeliana — dark green to brown, some injury 
Sasa senanensis - very few leaves green, all others brown and dead 
BROAD LEAVED EVERGREENS (SO CALLED) WHICH HAVE 
DROPPED MANY OF THEIR LEAVES BY APRIL 1943 
These plants then cannot be termed completely evergreen in the vicinity of Bostor 
Abelia grand iflora -leaves entirely dropped 
Akebia quinata - 
Berberis Julianae — 75% 
mentorensis — 5 % 
pruinosa - 50% 
Sargentiana - 25 % 
Cotoneaster adpressa — leaves entirely dropped 
glabra ta — 50% 

i Cotoneaster horizontalis - leaves entirely dropped 
lactea - 
i 6 6 6 66 66 
pannosa — 
Cyrilla racemiflora -50 °/o 
Kuonymus kiautschovica - c Z5°/o 
Iberis sempervirens — leaves entirely dropped 
Kalmia angustifplia ~ 50°/o 
Lonicera affinis pubeseens — 10 °/o 
japonica Halliana - leaves entirely dropped 
Mahoberberis Neuberti — b°fo 
Pyracantha coccinea Lalandii — all leaves brown and dead 
Viburnum buddleifolium - 10 °Jo 
rhytidocarpum — 25 °Jo 
rhvtidophylloides — 1 0% 
rhytidophyllum - 50 °/o 
NOTES 
Crab apples: The crab apples have been at their best all week and will con- 
tinue to be in full flower over the coming week end. Although the severe winter 
has seriously injured many shrubs in the Arboretum collections, none of the crab 
apples suffered except possibly M. Zumi calocarpa. There are two trees of this va- 
riety at the base of Peter’s Hill and both seem to be in very poor condition ; the 
trouble may prove to be fire blight and not winter injury, however. Normally 
M. Halliana Parlcmanii is the least hardy of all the Malus species and varieties, 
jbut this spring it was fairly well covered with flowers. The injuries observed from 
bhe unusually cold winter again prove that the crab apples are perfectly hardy in 
his northern climate and are to be recommended for planting everywhere in the 
North. 
It may be of interest to mention in connection with the crab apples, that a 
ather comprehensive survey of these important ornamentals has just been com- 
pleted and is now in the hands of the printer. All of the varieties known to be 
grown in North America are mentioned, sources where they may be purchased 
ire given, and as complete descriptions of flowers and fruits are given as is possi- 
ble under the somewhat limited space of the booklet, which approximates sixty 
bages. A history of the crab apples in North America is given together with a 
discussion of present experiments in hybridization, the new varieties being grown 
ind recommended for the colder areas of the mid-western United States and the 
irairie provinces of Canada. Further information concerning this booklet will be 
riven when it is issued a few weeks hence. 
Lilacs: As usual, lilacs were uninjured by the low temperatures of the past 
'inter. These are among the most hardy of shrubs and the majority of them 
hould be at their best by the week end of May 22. Cold weather has retarded 

their progress considerably this year. In fact, one Boston paper went so far as t< 
publish pictures in the rotagravure section (May 16) of the Lilac Path showing 
the plants in full bloom ; this was not due to any fault of the newspaper, but wa 
taken from information supplied by the Arboretum from records of previous years 
It is an excellent example of the difficulties one encounters in predicting from tin 
records of previous years just what may happen this season ; always we must con 
sider the idiosyncrasies of the New England weather. 
Shrub collection: Visitors to the shrub collection this year will notice tha 
every other grass path through its long lines of shrubs has been dug up and wil 
be kept under cultivation throughout the summer. This has been done in orde 
to eliminate fifty per cent of the work necessary in keeping proper display label 
on the plants and also to reduce the amount of grass cutting necessary. It will b 
possible now to use a power cultivator among these shrubs and so eliminate mud 
of the hand work which in the past has been so consuming. Like many other ini 
stitutions during this period, the Arboretum is confronted with a labor shortage 
making it impossible to keep the grounds in as good condition as in past years 
Young men on the labor force have left us or are about to be called into the Army 
and it is proving to be very difficult to replace them. 
With the very large amount of winter injury many plants are now conspicuou 
because of dead branches, this being especially true in the shrub collection, 'flies 
of course will be pruned later in the spring, but the work entailed will take con 
siderably longer than other years and will mean that much evidence of winter in 
jury will unfortunately be noticeable until summer. 
Clematis collection: One of the bright spots late this spring, we hope, will b 
the new clematis collection, planted along the fence at the far end of the lindei 
collection. Of some eighty plants placed there last fall, only seven failed to shoV 
new shoots by May 15. Since these were mostly old plants given us by the clem 
atis specialist, Mr. Louis Vasseur of Milton, they should produce a large numbe 
of blooms in the late spring and probably up to the end of June. The successfu 
wintering of these plants proves again that clematis can be grown in New Eng ! 
land. They may become diseased and die from various other causes, but if th 
results of this winter mean anything, the demise of a few plants cannot be lai< 
entirely to low temperatures. None of the plants were mulched but the base d 
each was surrounded with coal ashes to prevent mice from destroying the stem 
during the cold months. 
Equally successful results were obtained in our nursery, where we wintered 
about forty-five varieties of clematis given by a large grower last fall. These ha< 
merely t lie same protection as those mentioned above and weathered the winte 
with no greater percentage of loss. These were, moreover, much younger am 
smaller plants than those in the Vasseur collection, but apparently young plant 
are no more susceptible to low temperatures than are mature ones. 
Donald Wyman 
[ 24 ] 

ARNOLDIA 
A continuation of the 
Bulletin of Popular Information 
of the Arnold Arboretum, Harvard University 
Volume 3 JUNE 25, 1943 Numbers 5-6 
WINTER INJURY IN THE ARNOLD ARBORETUM, 1942-43 
L OW temperatures during the past winter have caused considerable injury to 
J trees and shrubs in the Arnold Arboretum, more injury than at any other 
time since the severe winter of 1933-34, when temperatures in Boston reached 
an all-time low. Last winter there were no strong winds, the soil was sufficiently 
moist at the time of freezing so that damage cannot be blamed on lack of mois- 
ture then. A study of the temperature records during the ten year period since 
1933 demonstrates that significant winter injury can be expected every year when 
temperatures of below zero are recorded at the Arboretum greenhouses. 
A complete listing was made of the plants suffering injury during the past win- 
ter and the lists of deciduous trees and shrubs are reproduced in this bulletin. A 
list of all plants suffering winter injury during the winter of 1941—42 is included 
since this was a very mild winter and excellent comparisons can thus be made. 
Not many evergreens were injured, and complete notes on them are to be found 
in Arnoldia 3: 21—23, 1943. In studying these lists, another group of lists should 
also be studied, these being made by Arnold Arboretum staff members after the 
severe winter of 1933-34 and published in the Bulletin of Popular Information, 
Series 4, Volume II, Nos. 7, 8, 9, 11, pp. 29-47 ; 55-60, 1934. These combined 
lists thus form a rather complete picture of the kind and amount of injury to be 
expected in mild and severe winters at the Arnold Arboretum. 
Minimum temperatures 
Maximum and minimum temperature readings are taken daily at the Arbore- 
tum greenhouses. It is interesting to note that a study of these shows that tem- 
peratures of below zero have been recorded in only three winters since 1933, and 
each time plants suffered considerable winter injury. The minimum temperature 
of the 1933-34 winter was— 17° F., during 1934-35 it was -8° F.,and the min- 
imum for last winter was —13° F. Winter injury may be due to any one of sev- 
eral factors, or to a combination of them, but from a study of the temperatures 
[ 25 ] 

and the reactions of the plants themselves it is safe to predict that serious injury 
will occur to plants when the temperatures drop below zero. By injury is meant 
the actual killing of flower buds, twigs, and branches. The typical “burning” 
of evergreen foliage can occur any winter regardless of the low temperature. If 
the ground is frozen and the air temperatures during the day are considerably 
higher than during the preceding night and high winds blow, optimum conditions 
for burning evergreen foliage occur. The minimum temperatures recorded at the 
Arboretum greenhouses are given below. These vary only a few degrees from the 
U.S. Weather Bureau official figures for Boston. It is interesting to note that on 
only seven days in 1933-34 and six days in 1942-43 did the minimum tempera- i 
tures fall below zero. Only one other time did the temperature go below zero 
nd that was seven days 
in January and February, 
1935 
1933 
191 $ 
December 28 
-4 
December 17 
-4 
29 
-17 
19 
—7 
30 
-14 
20 - 
-10 
21 
—5 
19 3 
19^3 
February 7 
—2 
F ebruary 1 5 - 
-13 
8 
0 
16 - 
1 1 
9 
-18 
10 
-3 
14 
-4 
In comparing the amount of injury done in these two winters, it should be kept 
in mind that there were consistently high winds throughout the winter of 1933-34 
which must have added materially to the killing of twigs and branches. There 
were no high winds last winter, nor was the soil too dry when it froze in the fall. 
However, there are 260 acres in the Arboretum grounds and temperatures are not 
uniform over the whole area. For instance, on December 29, 1933, when the 
thermometer at the greenhouse registered -17° F., one in the shrub collection a 
few hundred feet away (but considerably lower) registered —26° F. It is a known 
fact that injury is always more severe in the shrub collection on account of its 
low situation without sufficient air drainage. 
There is a question concerning the time the damage is actually done. It will 
be noted that in both years the temperatures were below zero in December and 
February, and lienee, theoretically, the damage could have occurred at either 
time. One instance seems to show that it may be the February cold spell which 
did the killing in 1942—43. Forsythia branches were taken in the greenhouse and 
forced after Christmas in December, 1942, and the flowers eventually came out 
in profusion, while branches cut again in late February failed to bloom. We also 
know that dormancy of many plants is a great deal more difficult to break by 
forcing in the greenhouse in December than it is in February. However, this 

interesting problem as to the exact time injury takes place should be investigated 
further. 
Explanation of lists 
The following lists constitute a complete survey of winter injury in the Arnold 
Arboretum during the past two winters, one a very mild winter and one a severe 
winter. Many of the plants killed to the ground are sending out new buds from 
ground level and will grow again; a few were killed completely, although it is 
still too early to determine this in all cases. Alb'izzia julibrissin rosea , for instance, 
suffered considerable injury. It was not until after June 6 that any branches 
showed life at all. On the other hand, Styraoc Obassia showed a normal growth of 
young shoots when examined on June 1, but after that date all new shoots sud- 
denly withered and died, thus indicating injury to the cambium layers of the 
main trunk. 
The plants growing in the Arboretum are divided into four groups, depending 
upon how seriously they were injured, i.e., plants killed to the ground, plants 
partially injured, flower buds only injured, and plants uninjured. It will be noted 
that some of the names are followed by percentages in parentheses. This is the 
amount of injury occurring in the winter of 1941 - 42 , and all plants injured dur- 
ing that season are so designated. It may be assumed that all other plants not 
so designated were uninjured during that winter. Though some discrepancies in 
the figures are difficult to explain, in most cases the injury in 1941—42 was con- 
siderably less than in 1942 - 43 . There was a much larger number of plants injured 
last winter than the previous one. 
In the second list the percentage figures without the parentheses represent the 
(approximate amount of twigs and branches killed. This naturally varies among 
the plants and the places where they are growing in the Arboretum, but the fig- 
:ures given are comparable. 
I In the third list, plants with flower buds killed, the percentages not in paren- 
theses represent the approximate number of flower buds on the entire plant which 
were killed. It is reasonable to surmise that those plants listed as having more 
than fifty per cent of their branches killed would also have few, if any, flowers. 
Plants in this group are naturally those in which the flower buds are formed doi- 
ng the previous summer and are thus present all winter. It will be noted that 
such plants normally bloom from early spring to mid- June, including some of our 
jnost colorful ornamentals, among which are the forsythias, the oriental cherries, 
he magnolias, the wisterias, the azaleas, and the rhododendrons. Plants blooming 
ater in the summer usually form their flower buds on the current year’s growth, 
l All species at present growing in the Arboretum, not included in these lists, 
were uninjured by the winter cold. However, the mere listing of these would 
ake too much space and would serve no important need; there is, of course, al- 
vays the question, especially in the minds of those not familiar with the Arnold 
Vrboretum, as to whether a certain species is actually growing there. To empha- 
ize the fact that certain questionable plants did come through last winter unin- 

jured, a fourth list has been included. Not all plants of the thousands of uninjured 
ones could be included in this publication, but the few in the fourth list may prove 
to be of interest to those who are interested in hardy trees and shrubs. 
1. PLANTS KILLED TO THE GROUND DURING THE 
WINTER OF 1 942-43 
(The heights given represent the size of the plants killed. The fact that a six 
foot plant is killed to the ground represents a considerably greater injury than 
the killing of a younger plant of the same species which is only one foot high. 
The figures in parentheses denote the pen 
ing the comparatively mild winter of 1941 
Abelia Engleriana 5 7 
Goucheri l 7 
grand iflora 5 7 
Acanthopanax leucorrhizus 7 7 
Acer japonicum aconitifolium 10 7 
Oliverianum 4 7 
Actinidia chinensis 2 7 
melanandra 4' ( 80 ) 
polygama 4 7 
Alnus Maximowiczii 2 7 
Amorpha croceo-lanata 
fruticosa tennessensis 
glabra 
Baccharis halimifolia 6 7 (2 0 ) 
Berberis aggregata Prattii 5 7 ( 15 ) 
recurvata 3 7 (30) 
i i Autumn Cheer” 3 7 
Beaniana 5 7 
buxifolia nana 3 7 
candid u la l 7 
Chenaultii 3 7 
Fendleri 
Fireflame” 4 7 
Gagnepainii 3 7 
polyantha 3 7 
vubrostilla 2 7 
Sargentiana 5 r 
Wilsonae Stapfiana 6 7 (, 30 ) 
subcaulialata 5 7 
Berchemia racemosa 8 7 (so) 
Buddleia - all except alternifolia 
ventage in amount of winter injury dur- 
-42.) 
Callicarpa - all species in collection 
6 - 8 7 ( 25 ) 
Campsis grandiflora Thunbergii 2 7 
(80) 
Ceanothus pallid us roseus 2 7 (jfO) 
Celastrus gemmata 6 7 (90) 
hypoleuca 6 7 (80) 
Celtis Tournefortii 3 7 
Chaenomeles lagenaria cathayensis 
3 7 (90) 
Clematis species and varieties 6-8 7 
Clerodendron trichotomum 1 0 7 (80) | 
Colutea - all species and varieties 6-8 7 
(20-80) 
Coronilla Emerus 4 7 
Corylopsis platypetala 10 7 
spicata 6 7 
Veitchiana 10 7 
Cotoneaster affinis bacillaris 8 7 
amoena 2 7 
conspicua 4 7 
microphylla l^ 7 
rotundifolia 3 7 
rubens 3 7 
salicifolia rugosa 4 7 
Cytisus “Burbank hybrids” 6 7 (20) 
sessilifolius 8 7 
Decaisnea Fargesii 6 7 (AO) 
Deutzia Avalanche” 4 7 
candelabrum 5 7 
Candida 4 7 (j/.0) 
t -28 ] 

Deutzia earnea 3' {j. 0 ) 
densiflora 4' {25) 
stellata 4' 
* ‘Contraste” 6' 
elegantissima 6' 
fasciculata 4' {60) 
glomeruliflora 5' 
hypoleuca S' ( 80 ) 
kalmiaeflora 9' 
longifolia and vars. 4' ( 50 ) 
“Magicien” S' 
magnifica and vars. S'— 9' {60) 
mollis 4' 
“Mirabilis” 5' 
myriantha 8' 
reflexa S' 
rosea and vars. 4'—Q' { 80 ) 
I scabra and most vars. 4'— 6' {30) 
Sieboldiana and var. 5' 
i Vilmorinae S' 
)ipelta floribunda 19' 
ventricosa 5' 
r raxinus Paxiana 4' 
xaylussacia brachycera \' 
Genista cinerea 9' 
irewia biloba 10 r {90) 
ielwingia japonica 4' 
lovenia dulcis 95' 
lydrangea arborescens and vars. 3‘ 
cinerea and var. S' 
quercifolia 4' {15) 
radiata 9' 
lex Aquifolium S' 
yunnanensis ( ‘large leaf”) \' 
(“small leaf” - no injury) 
ndigofera amblyantha \0' 
werria japonica and vars. 4' {25-80) 
-agerstroemia indica (Cole’s 
hardy” variety) S' 
avandula officinalis \' 
espedeza bicolor 4' 
, japonica 6' 
Thunbergii 6' 
Ligustrum acuminatum macrocarpum 
ovalifolium aureo-marginatum {50) 
sinense 10' {SO) 
Lindera obtusiloba 10' 
praecox 19' 
Lonicera affinis pubescens 5' ( 70 ) 
alseuosmoides 1' 
dioica S' 
etrusca 3 ' {70) 
gynochlamydea 5' {^0) 
Henryi 9' 
involucrata serotina 4' {20) 
Myrtillus 9' {60) 
obovata S' 
orientalis longifolia 10' {25) 
Periclymenum belgica 4' {50) 
quinquelocularis 9' {25) 
translucens 8' 
saccata {50) 
Standishii lancifolia 6' 
IVlarsdenia erecta S' 
Meliosma Beaniana 15' 
Neillia ribesioides 7' 
sinensis S' (80) 
Parrotiopsis Jacquemontiana 8' 
Periploca laevigata 8' 
Philadelphus argyrocalyx S' 
“Dame Blanche” 4' {30) 
Lemoinei “Coupe d ’Argent” S' 
subcanus Q' {50) 
Photinia Beauverdiana notabilis 4' 
Physocarpus capitatus 6' {15) 
Pleioblastus distichus S' 
Polygonum baldschuanicum S' 
Prunus Laurocerasus schipkaensis 4' 
Quercus kewensis 4' 
Rhamnella franguloides 4' 
Rhododendron indicum laciniatum l' 
“Katie” 9' 
“Nellie” 9' 
Rosa Brunonii 9' 
Davidi 9' 
Henryi 9' 
[ 29 ] 

Rosa Luciae 2 ' 
mollis 2 7 (60) 
“Morica” S' 
Noisettiana S' (5 0 ) 
omeiensis chrysocarpa 2 ' ( 30 ) 
pteracantha (70) 
sempervirens l 2 ' 
Serafinii 1 ' (50) 
Woodsii and var. 2' 
Sasa senanensis 6 ' (oO) 
Sophora viciifolia 8 ' ( 20 ) 
Spiraea albiflora (1/.0) 
Blumei 4' (lo) 
brachybotrys S' (25) 
Bumalda Froebeli 2' (25) 
japonica microphylla 2' (50) 
r uberrima 2 ' 
Miyabei glabrata S' (30) 
mollifolia 7 ' 
revirescens S' (70) 
rubra S' 
Sargentiana 5' 
Zabeliana 4' 
Stephanandra incisa 5' (50) 
Tanakae 4>' 
Vaccinium Vitis-idaea l' 
Viburnum buddleifolium 6 ' 
ovatifolium 10' 
rhytidophyllum and var. 4 / -9 / 
Vitex Negundo incisa 6 ' - 8 ' 
Vitis Piasezkii Pagnuccii 8' 
pulchra 8' (90) 
Weigela hortensis 5' 
japonica sinica 7 ' 
Zanthoxylum simulans S' (90) 
II. PLANTS PARTIALLY INJURED DURING THE WINTER OF 1942-43 
(The figures represent percentage in amount of winter injury ; the figures in 
parentheses denote the amount of winter injury during the comparatively mild 
winter of 1941-42.) 
Acanthopanax setchuenensis 95 
Simonii 50 
ternatus 95 
Albizzia julibrissin rosea 50-98? 
Amorpha brachycarpa 90 
canescens 50 
fruticosa 75 
nana 80 
Artemisia sacrorum 25 
Berberis aemulans 75 
aggregata 80 
“Barbarossa” 10 
dictyophylla 50 
Julianae 90 
morrisoniensis 50 
triacanthophora 80 
verruculosa 50 
vulgaris atropurpurea 25 
wokingensis 50 
Calluna vulgaris vars. 10-50 (10-50) 
Calycanthus fertilis 25 
floridus ovatus 50 
Caragana Boisii 15 
Chamlagu 50 
densa 50 
frutex 20 
pekinensis 25 
Ceanothus americanus 75 ( 4 . 0 ) 
ovatus 25 
pubescens 40 
Cephalanthus occidentalis 90 (50) 
Cercis chinensis 50 
Chaenomeles lagenaria “Cardinalis” 
10 
“Marmorata” 40 
Wilsonii 50 
superba 25 (20) 
Chionanthus virginicus 30 
[ 80 ] 

Clethra acuminata 5 
alnifolia 10 
Corema Conradii 25 ( 30 ) 
Cornus australis Koenigii 50 
Cotoneaster apiculata 50 ( 30 ) 
Dielsiana 50 
Henry ana 75 
horizontalis 50 
perpusilla 50 
Wilsonii 7 5 
rotundifolia 50 
Zabeli 50 
Corylopsis pauciflora 50 
Cyrilla racemiflora 50 
Cytisus praecox 75 
purgans 75 
supinus 75 
Davidia involucrata 50 ? 
Deutzia candelaburm fastuosa 25 
I discolor 50 
major 50 
gracilis 75 ( 30 ) 
hypoglauca 75 ( 30 ) 
Lemoinei 30 
compacta 30 ( 30 ) 
parviflora ovatifolia 25 
I scabra ‘‘Pride of Rochester” 50 
Schneideriana laxiflora 75 
Oiervilla rivularis 20 ( 20 ) 
irica carnea 90 
iuptelea polyandra 25 
ivodia Daniellii 30 
ixochorda Korolkowi 30 
racemosa 25 
r ontanesia Fortunei 50 
'orsythia suspensa 10 
jaylussacia baccata 10 
glaucocarpa 20 
dumosa 90 
frondosa 1 0 
ienista radiata 50 ( 25 ) 
lamamelis macrophylla 50 
Helianthemum nummularium vars. 50 
Hypericum densiflorum 50 
frondosum 20 ( 60 ) 
Kalmianum 20 
prolificum 20 
Iberis saxatilis 30 
sempervirens 50 
Idesia polycarpa 50 
Ilex crenata 50 
decidua 50 ( 90 ) 
rugosa 75 
serrata 75 ( 40 ) 
Itea virginica 80 ( 50 ) 
Jamesia americana 10 
Laburnocytisus Adami 75 
Leucothoe racemosa 10 
Ligustrum acuminatum 10 
ibolium 25 
Ibota nana 80 
insulare 25 
obtusifolium 25 
ovalifolium 75 
Quihoui 10 
pendulum 50 
vulgare 30 
‘ ‘ Lodense” 75 
pyramidale 50 
sempervirens 50 
Lindera Benzoin 30 
Liquidambar Styraciflua rotundiloba 
30 (This is a small plant obtained 
from North Carolina) 
Lonicera alpigena 10 
Altmannii pilosiuseula 10 
chrysantha Regeliana 10 
deflexicalyx 50 ( 30 ) 
fragrantissima 25 
Heckrottii 30 
heteroloba 10 
Korolkovii 30 
microphylla 25 
Morrovvii 10 
[31 ] 

Lonicera Purpusii 10 
syringantha 50 
thibetiea 10 
Vilmorinii 50 {70) 
Webbiana 30 
xylosteoides 10 
Lycium chinensis 10 (20) 
halimifoliura 50 (25) 
ruthenicum 50 
Lyonia mariana 40 ( J/.0 ) 
Myrica Gale 50 
Paulownia tomentosa, small trees to 
ground, large trees only 25 
Periploca graeca angustifolia 75 
Pertya sinensis 75 
Philadelphus “Bonje” 75 
Burkwoodii 90 
coronarius pumilus 50 
cvmosus “Conquete” 25 {l^O) 
cymosus “Nuee Blanche” 25 
“Rosace” 25 (SO) 
Lemoinei 50 {20) 
“Amalthea” 50 
Avalanche” 50 
“Belle Etoile” 90 ( 50 ) 
erectus 50 
“Innocence” 50 {2o) 
“Mont Blanc” 50 
Lewisii 75 
Magdalenae” 50 
nepalensis 25 {20) 
Norma” 25 
“Pavilion Blanc” 50 
purpureo-maculatus Sybille” 
sericanthus 50 {SO) 
Sylvanae” 75 
virginalis “Argentine” 10 {80) 
“Glacier” 80 
Phvsocarpus intermedius parvifolius 
10 
stellatus 50 {20) 
Poncirus trifoliata 50 
Potentilla fruticosa 30 
micrandra 1 0 
ochroleuca 25 
parvifolia 25 (40) 
tenuiloba 10 
Veitchii 10 
Prunus concinna 25 
Fontanesiana 25 
Persica and vars. 50 
(except var. pendula which was 
uninjured) 
pilosiuscula 60 
pumila susquehanae 25 
serrula 20 
serrulata, no vars. had any flowers 
and all apparently suffered se- 
vere twig injury as evidenced 
by many leaf buds failing to 
open by June 1 
“Kwanzan” 75 
subhirtella 50 
autumnalis, intermittent injury 
all along twigs 
pendula 50 
Pterocarya hupehensis 50 
Pyracantha coccinea Lalandii, foliage 
only killed 
Quercus Schochiana 50 
Rhododendron obtusum japonicum 
hybrids 25-100 
A rn old i an um 10 
Kaempferi 10 
Rhodotypos scandens 50 
Ribes diacanthum 25 
futurum 50 {SO) 
petraeum Biebersteinii 50 
robustum 50 
Rosa arvensis 50 
caudata 50 
centifolia 50 
foetida bicolor 25 
Helenae 50 

Rosa Lheritierana 75 
multibracteata 50 
multiflora 10 
rugosa “Max Graf” 50 
“Rustica” 10 ( 30 ) 
spinosissima fulgens 50 
pimpinellifolia 10 
“Plato” 50 
“Pythagoras” 25 ( 50 ) 
Watsoniana 50 ( 50 ) 
Wichuraiana 75 
3ubus deliciosus 50 (20) 
Securinega suffrutieosa 50 
Sorbaria arborea vars. 10-95 
. sorbifolia vars. 50— 75 
Spiraea alba 50 
areuata 50 
arguta 25 
betulifolia 50 (SO) 
Billiardii 50 ( 50 ) 
! cantoniensis 75 (60) 
chamaedryfolia 30 
cinerea 30 ( SO ) 
corymbosa 50 
Douglasii 50 (25) 
fontenaysii alba 10 
rosea 25 
Foxii 50 
- Fritschiana 30 
gemmata 25 
Henry i 50 
hypercifolia and var. 25 (20) 
inflexa 25 (20) 
japonica 10 
atrosanguinea 50 (40) 
ovalifolia 25 (50) 
laevigata 50 
latifolia 25 (30) 
j lucida 10 
Margaritae 50 
media and var. 25 
Menziesii 50 
multiflora 25 
nipponica 50 
nudiflora 10 
oxyodon 20 
pachystachys 50 (SO) 
prunifolia 25 
pubescens 10 
pyramidata 30 
Rosthornii 90 
salicifolia 20 
Schinabeckii 50 
semperflorens 75 
superba 50 
triloba ta 50 
uratensis 25 
Vanhouttei 20 
Veitchii 20 
virginiana serrulata 10 
Staphylea colchiea and vars. 75 
Stewartia sinensis 50 
Symphoricarpos albus laevigatus 10 
( 15 ) 
Chenaultii 75 ( 50 ) 
hesperius 50 
orbiculatus and var. 50 (30) 
Syringa emodi 50 
Taxus chinensis 30 
Ulmus earpinifolia Dampieri 10 
suberosa 10 
hollandica 30 
major 30 
Vaccinium corymbosum 10 
hirsutum 25 
Viburnum Burkwoodii 2 
erosum 25 (20) 
erubescens 90 
hupehense 80 
Vitex Agnus-castus alba 50 (90) 
Doaniana 50 
Weigela “Andre Thouin” 20 (#0) 
“E. Andre” 10 ( 60 ) 
florida 10 
Congo” 25 
variegata 25 (80) 
[33] 

Weigela 4 4 M arc Tellier” 10 
“Pres. Duchartre” 20 
4 4 Seduction” 50 
“Vanhouttei” 50 (7 0) 
“Verschaffelti” 20 (So) 
Zanthoxylum schinifolium 50 
Zenobia pulverulenta 50 (20) 
Zizyphus jujuba 10 
III. PLANTS WITH FLOWER BUDS ONLY INJURED DURING 
THE WINTER OF 1942-1943 
Figures denote percentage of injury 
Abeliophyllum distichum 0-75 
Amelanchier canadensis 15-50 
Cornus florida 25 Flower clusters have 
the two bracts (outside of bud) in- 
jured and stunted in many cases. 
Corylopsis glabrescens 100 
Daphne Mezereum 100 
Forsythia europaea 10-90 
japonica saxatilis 50 
ovata 75 
X europaea 50-75 
all others 100 
Hamamelis mollis 100 
Lonicera fragrantissima 75 
praeflorens 100 
Magnolia denudata 10 
Soulangeana “ Alexandrina” 30 
“Candolleana” 25 
“Norbertiana” 25 
rubra 75 
stellata 25 
Pieris japonica 100 
Prunus apetala 95 
avium 90 
canescens 90 
cerasifera and vars. 95 
cone inn a 100 
cyclamina 100 
Davidiana and vars. 100 
incisa and vars. 75-90 
insititia 99 
Juddii 90 
mandshurica 75 
Maximowiczii 100 
nipponica kurilensis 7 5-95 
Sargenti 75-90 
Schmittii 90 
serrula 100 
serrulata and most vars. 90-100 
tomentosa and vars. 90 
triloba multiplex 99 
yedoensis 100 
Rhododendron arbutifolium 90 
catawbiense, many hybrids 25-75 
4 ‘Cunningham’s White” 100 
dauricum 100 
sempervirens 100 
Fortunei hybrids 20-100 
gandavense many vars. 75 
indicum crispiflorum crosses 100 
laetevirens 90 
molle, many vars. 75 
mucronulatum 99 
obtusum amoenum 95 
arnoldianum 95 
Kaempferi 95 
Schlippenbachii 100 
viscosepalum 75 
yedoense poukhanense 75 
Viburnum fragrans 100 
Wisteria sp. 100 
[ 34 ] 

IV. PLANTS UNINJURED DURING THE WINTER OF 1942-43 
Note: It is usually presupposed that all plants not recorded in “injured” lists 
tvere not injured. Such is the case with these lists. However, to be certain that 
some interesting plants are definitely recorded as uninjured, the following list is 
jfFered . ) 
\lyssum gemonense 
3etula papyrifera and vars. 
3ampsis radicans 
>stanea mollisima 
Nereis canadensis 
"elastrus flagellaris 
orbiculata 
scandens 
Jiaenomeles japonica Corallina” 
sanguinea 
ihamaedaphne calvculata 
)aphne altaica 
Cneorum and vars. 
Somerset” 
)eutzia coreana 
glabrata 
grand iflora 
parviflora 
staminea 
Jirca palustris 
nkianthus campanulatus 
ymnocladus dioicus 
[amamelis vernalis 
[ibiscus syriacus vars. 
ex montana 
yunnanensis 
almia latifolia 
olkwitzia amabilis 
espedeza kiusiana 
iquidambar Styraciflua 
[acludrania hybrida 
laddenia hypoleuca 
agnolia Kobus 
salicifolia 
Soulangeana speciosa 
verbanica 
“Waterlily” 
Mahonia Aquifolium 
repens 
Oxvdendrum arboreum 
Paeonia suffruticosa 
Periploca sepium 
Pieris floribunda 
Prinsepia sp. 
Prunus americana 
Besseyi (heavy bloom) 
cerasus austera 
domestica Julianae 
glandulosa 
Munsoniana 
“Newport” 
nigra 
Padus vars. 
salicina 
spinosa 
tenella var. 
Pyrus communis Pyraster 
pyrifolia 
ussuriensis hondoensis (very few 
flowers) 
ovoidea 
Rhododendron atlanticum 
“Boule de Neige” 
calendulaeeum 
canadense 
carolinianum 
X mucronulatum 
catawbiense 
album 
Fraseri 
“Fiirst Camille von Rohan” 
“Henrietta Sargent” 
[ 35 ] 

Rhododendron “Heureuse Surprise” 
4 ‘imperialis” 
japonicum 
narcissiflora 
nudiflorum 
“Pallas” 
“Pucella” 
roseum 
Smirnowii 
speciosum 
Vaseyi 
Rhus aromatiea 
Ribes aureum and vars. 
odoratum and vars. 
Rosa Ecae 
Hugonis 
Primula 
rugosa and most vars. 
spinosissima 
Spiraea prunifolia simpliciflora 
Thunbergii 
Staphylea holocarpa 
Stewartia koreana 
Symplocos paniculata 
Tripterygium Regelii 
Viburnum rhytidophylloides 
Vinca minor and vars. 
Xanthorhiza simplicissima 
Zanthoxylum americanum 
[ 36 ] 

ARNOLDIA 
A continuation of the 
Bulletin of Popular Information 
of the Arnold Arboretum, Harvard University 
Volume 3 JULY 2, 1943 Number 7 
GHENT HYBRID AZALEAS ARE HARDY IN NEW ENGLAND 
T HESE are probably the most beautiful of all the great group of azaleas, but 
curiously enough, comparatively few are to be found in the gardens of New 
England. Many have felt them to belong in the class of tenderer shrubs, while 
others have believed them too much of a hazard for the amateur to attempt, es- 
pecially as the initial price seems high. Then, too, they have been often difficult 
to obtain. 
True it is that the novice, just beginning the cultivation of azaleas, is wisely 
advised to start with our own native species as being the hardiest and surest of 
success. Rhododendron calendu/aceum, for example, probably the finest with its 
range of color from pale yellow to orange and crimson, and with its long season 
of bloom is so sturdy, that granted the simplest requirements of practically all 
azaleas, will survive the rigors of the coldest winter and many abuses beside. 
Another native, the lovely shell pink R. Vaseyi from the Carolina mountains, is 
equally sturdy, while R. nudijlorum , R. roseum , R. arborescens and R. viscosum , noted 
for their exquisite fragrance as well as beauty, deserve to rank with the best and 
strongest of our native shrubs. 
Azaleas from the Orient — such as R. mol/e , R. obtusum varieties japonicum and 
Kaempferi , R. Schlippenbachii , R. mucronulatum — with their various colors, are de- 
servedly great favorites in our gardens and have been widely planted with vary- 
ing degrees of success. Hybrids of R. molle and R. obtusum japonicum have been 
particularly popular, though not rewarding as to hardiness. But the Ghent hybrid 
in abundance is likely to be missing, not only from the garden collection but from 
many nursery catalogues as well. 
The history of the creation of this valuable class of azaleas is a fascinating one, 
but suffice it to say here that Ghent hybrids (R. gandavense) are the results of 
crossing the only European species, the large yellow Pontic Azalea ( R . luteum or 
Azalea pontica) from the regions of the Black Sea with the American Flame Azalea 

(/?. calendulaceum ) and Pinxterbloom ( R . nudiflorum ); sometimes also with the! 
Swamp Azalea ( R . viscosum) and the Sweet Azalea (R. arborescens). Though the ! 
first experiments were made in England early in the nineteenth century, the de- 
velopments of lasting importance came out of Ghent in Belgium in about 1825: 
and many are the beautiful offspring of this magnificent accomplishment. The 
species seems to possess so many virtues! — a bewildering range of color running 
from creamy white through pale yellow and pink, salmon and rose, to flaming 
orange and red ; fine form, which applies not only to the flowers — large in some) 
varieties, medium or small in others, single, double, hose-in-hose” — but also to 
the rich foliage and the shrub itself which may in many varieties grow to six oil 
seven feet in height and nearly as wide. Then, too, they have that important 
asset, delicious fragrance, and last but not least, proven hardiness. This last state- 
ment is made after twenty-four years of experience in growing them, as well as! 
close observance of the plantings in the Arnold Arboretum. 
These plants in the Arboretum were very likely the first large shipments im- 
ported into this country, coming in 1918 and 1914: — from Veitch in England, 
the rosy 4 ‘Beaute Celeste,” “Cardinal” and “Flamboyant” ; from Wezelenburgj 
in Holland, “Fiirst Camille von Rohan,” “General Trauff,” “Minerva,” beau- 
tiful salmon rose, the extraordinarily brilliant “Pallas,” k ‘ Pucelle,” the crimson! 
“Josephine Klinger,” and the delicate “Heureuse Surprise”; from Koster, the 
brilliant red “Comte de Flandre,” the lovely “Aurore de Rovghem,” the dark 
“Julius Caesar” and many others. “Gloria Mundi” always stands out as a mar- 
vel of orange magnificence ! 
Besides these in the Arboretum many plants went to nurseries and thence tc* 
private growers. One hears that a large percentage of the latter were lost, due tcj 
owners not realizing what these rare specimens required in the way of soil, nuf 
trition and natural surroundings. Fortunate it is that those in the Arboretun 
flourished, and now produce one of the most magnificent displays of any kind tc 
be seen anywhere in May and June! And fortunately, too, enough of those if 
private hands survived to demonstrate what a satisfactory shrub this can be, be 
cause Plant Quarantine No. 87 — effective June 1, 1919 — cut short the importa 
tion of all nursery stock with soil about the roots of the plants, and so our nurseries 
were thrown on their own to keep alive and propagate these valuable hybrids. 
The experience of this writer has been to find them infinitely more satisfactory 
in every way than the Oriental species; i.e., R. molle, R. Schlippeubachii, R. ob 
tusum japonicum, and even R. obtusum Kaempferi. We had some hundred of thes( 
R. gandnvense hybrids installed in 1919 with almost no loss in Brookline and also:! 
in Ma ine, sixty miles north-west of Portland, where in winter the temperatun 
drops anywhere from ten to forty degrees below zero. Yet not only have th< 
plants proved hardy, but the flower buds have survived as well. 
The situation in which these have grown have not been uniform by any mean: 
except for the one required fundamental condition — acid soil with plenty of lea'' 1 

mold and humus, and protection from hot winds. For instance, “Narcissiflora, ” 
the beautiful pale yellow “hose-in-hose” variety grows six feet tall under tall red 
pines at the eastern edge of the lake at Bryant Pond, Maine, while underneath 
and growing lower are the brilliant vermillion “Coccinea Speciosa,” the clear 
yellow “Nancy Waterer” and orange ‘ Unique.” Cold icy winds tear down the 
lake in winter, but still these lovely things persist happily. In another spot more 
secluded, on a gentle slope going to the lake on the south side, these same vari- 
eties mixed with the native R. arborescens thrive so happily that they seem as at 
home as the old white pines and maples under which they grow. Across the lake 
on the side of a sheer wooded mountain are more varieties growing perhaps not 
so tall, but sturdily nevertheless. The lovely Japanese Torch Azalea also is here 
but its growth is not so vigorous. 
No weeding was necessary after the first year and no feeding has ever been 
given them, the annual dropping of the soft pine needles making a natural pro- 
tective mulch and a continuous source of supply. In Brookline, on the other hand, 
cottonseed meal has been applied to the soil from time to time, and a fall mulch 
of oak leaves added. 
Perhaps the most amazing of all are the specimens which have grown in Maine 
in a bog by the pool in the sunken garden. This is a natural pool which rises and 
falls with the changes of water level of the lake, and in spring the roots of the 
azaleas are almost surely in water. The plants are exposed to full sun practically 
all of the day until September — the best possible condition of course for setting 
buds. Here is really a brilliant spectacle when “Minerv r a” and “Bouquet de 
Flore” both salmon rose and the pale “Raphael de Smet” cover their branches 
with a miracle of bloom and fragrance. The trunks of these shrubs are one to two 
inches thick and the side branches grow so well that long sprays may be used for 
cutting each year. This also keeps the plant from getting “leggy.” Below are 
the fragrant Swamp Azaleas, absolutely at home, yet a few yards away not a hy- 
brid tea rose will survive a winter, having to be sunk not two, but four feet in 
the fall, so deep does the frost penetrate the ground. Also it has been found that 
none of the true rhododendrons can be grown in this locality, yet the supposedly 
tender R. gandavense hybrids live and like it ! 
It is no news that azaleas can be moved in full bloom, but we put some of these 
to a terrific test when we dug many of our tallest treasures in August at Bryant 
Fond, Maine, balled them and sent them to Brookline, Massachusetts in a closed 
truck. The day they were dug a sudden change in the weather sent the tempera- 
ture into the nineties for five cruel days, yet all survived and bloomed profusely 
in the spring, and for two years gave no evidence of the shock they had received. 
However, conditions in Brookline were not nearly so ideal, and at the end of that 
time the two main stalks showed no signs of approaching death. Accordingly these 
were cut to the ground and have since grown into new vigorous plants which are 
now thriving. This ability to *keep going” after a severe pruning of the dead 

wood is a valuable characteristic in these azaleas as it is fortunately in many other 
deciduous shrubs. No one should decide too quickly that an azalea is dead merely) 
because the main branches look dead. 
If one would multiply these hybrid treasures, the layering process is to be rec- 
ommended. “Irene Koster” a very beautiful but tender and temperamental hy- 
brid — of which out of a thousand imported to this country only six are now known 
to be alive — thus far having defied all the improved methods of propagation by 
cuttings, has finally been successfully multiplied by layering. Two years is neces-i 
sary before severing the layer from the main plant in order to obtain an adequately 
strong root system. 
This past difficult winter has brought one of the severest possible tests to all 
flowering shrubs (a rare winter indeed when Forsythia buds are killed !) and it 
was probably one of the worst about here for azaleas. Rhododendron mucronulatum 
failed to bloom; R. Sch/ippenbachii, another early Korean was poor; R. mode va- 
rieties had many flower buds killed ; and R. obtusum Kaempferi had flowers in evi- 
dence only below the snow line — all the more apparent after last year’s glorious 
array ! 
On the other hand, all the azaleas native to northeastern United States bloomed 
well this spring, (see Arnoldia 3: 25-36, 1943) with practically no evidence of 
winter injury. 
Coming in far ahead of the orientals and second only to our natives were the 
R. gandavense hybrids — not a hundred percent bloom to be sure, but with flower 
buds hardy enough to be considered as among the hardiest of azaleas for our New 
England climate. 
All of which goes to show that the native blood in this fine hybrid species is 
the answer! More and more are hybridizers coming to eliminate the tender R. 
luteum strain and are substituting these strong native parents. Worth while re- 
sults may be expected along this line. 
Now one hopes that many more nurseries will be encouraged to carry these on 
and that more individuals will know them better through living close to them. 
Surely they will add even more glory to our great season of flowering shrubs! 
Bessie Collier Ellery 
(Mrs. William Ellery) 
M rs. Ellery, past President of the Chestnut Hill Garden Club, has been grow- 
ing magnificent Ghent Azaleas in Maine and in Brookline for many years. They 
have survived intense winter cold astonishingly well. What she has to say about 
them indicates their hardiness, adaptability and desirability for planting through- 
out New England. — Ed. 

ARNOLDIA 
A continuation of the 
Bulletin of Popular Information 
of the Arnold Arboretum, Harvard University 
Volume 3 SEPTEMBER 17, 1943 Number 8 
CRAB APPLES FOR ORNAMENTAL FRUIT 
N OW is the time of year when the fruits of the crab apples color brilliantly, 
red and yellow. Some varieties are outstanding, retaining their colorful 
fruits for long periods, others are mediocre in this respect, and still others have 
fruits that remain green until they fall from the trees. Some of the crab apples 
we value for their beautiful flowers alone, such as the double flowering varieties 
of Mains ioensis , M. Halliana Parkmanii , M. hupensis , “ Katherine’' and 4 4 Prince 
Georges,” the last two of which are new double flowering varieties. However, 
these do not have brilliantly colored fruits. In a few forms, such as “Bob White,” 
the small fruits remain on the trees throughout the winter, and these supply a 
source of food for certain winter birds. 
Then there are some like “Beauty,” “Bob White,” Mains brevipes and M. 
toringoides which are valued for their colorful fruits but which are not especially 
prominent in flower when compared with the better flowering varieties. The best 
of these useful trees, however, is that group which includes the species and va- 
rieties noted for both colorful flowers and fruits, such as M.arnoldiana , M.baccata , 
“Flame,” M. floribnnda , “Hopa,” “Joan,” “Montreal Beauty,” the M. purpurea 
varieties aldenhamensis , Eleyi , and Lemoinei , 4 Itedflesh,” M. robust a percisi folia, 
Sissipuk,” M. Zumi calocarpa . 
In many old orchards one used to find certain crab apple trees grown for eco- 
nomic purposes, chiefly for making preserves and jellies. “Hyslop,” “Transcend- 
ent,” and 44 Whitney” are probably the best of these, but 44 Florence” and 
44 Early Strawberry” are available from one or two nurseries in this country. 
Modern methods of manufacture and selling have largely eliminated the old- 
fashioned practice of growing crab apples in the home orchard, for it has become 
far easier to go to the corner grocery and buy crab apple jelly which has been 
manufactured in car load lots, than to grow trees and manufacture one’s own 
supply from fruit collected in the home orchard. 
[41 ] 

Dates between which crab apple fruits are colorful and effective 
These dates were recorded during 1942 at the Arnold Arboretum and have 
been corroborated by observations made in other parts of the United States. 
© =only green fruits and dropping on this date 

Aug 
Sept 
Oct 
Nov 
Dec 
Jan 
Feb 
lancifolia 
0 
x magdeburgensis 
MAKAM1K 
MATHEWS 
0 
MERCER 
0 
x micromalus 
MONTREAL BEAUTY 
OLGA 
platycarpa 
0 
prunifolia 
prunifolia fastigiata 
prunifolia Rinki 
pumila 
0 
pumila Niedzwetzkyana 
x purpurea 
x purpurea aldenhamensis 
x purpurea Eleyi 
QUEEN CHOICE 
REDFLESH 
x robusta 
Some 
cions 
until 
X 
x robusta erecta 
x robusta percisifolia 
Sargenti 
Sieboldii 
Sieboldii arborescens 
x Soulardii 
0 
spectabilis 
spectabilis Riversii 
x sublobata 
sylvestris 
0 
toringoides 
Tschonoskii 
0 
x Zumi 
x Zumi calocarpa 
© = only green fruits and dropping on this date 
Bold face type — botanical species and varieties 
Large capitals — outstanding horticultural varieties 
Small capitals — lesser horticultural varieties 
[ 43 ] 

Newer varieties of economically valuable crab apples are becoming available 
through a few nurseries in the United States and Canada. Among these varieties, 
some of which are ornamental as well as useful are “Bedford,” “Columbia,” 
“Dolgo,” “Osman,” “Rosilda,” “Scugog,” “Wynema” and “Young Amer- 
ica.” Some of these are grown for their fruits in place of standard apple varieties 
in the colder parts of Canada where ordinary apples are not hardy. 
The length of time that the species and varieties retain their colorful fruits on 
the trees is of great interest and the chart, pp. 42-43 shows some of the data col-' 
lected in the Arnold Arboretum last year. The length of time the fruit remains 
colorful may vary from year to year, but these data represent the normal fruiting) 
season of 1942 and are reprinted from CRAB APPLES FOR AMERICA, recent- 
ly published by the American Association of Botanical Gardens and Arboretums. 
Notes of Interest 
CRAB APPLES FOR AMERICA by Donald Wyman, published by the Amer- 
ican Association of Botanical Gardens and Arboretums is an 81 -page booklet giv- 
ing detailed information concerning the 260 varieties of ornamental and economic 
crab apples now being grown in North America, together with sources where they 
may be obtained. The booklet is the result of a survey made by a committee of 
the American Association of Botanical Gardens and Arboretums, thus bringing! 
together the combined experiences of this committee and other available infor- 
mation concerning this valuable group of ornamental trees. 
This booklet should be owned by everyone interested in growing crab apples 
for it contains much practical information and will serve as an excellent reference 
work on this subject. It may be obtained for one dollar from the Arnold Arbore- 
tum, Jamaica Plain, Massachusetts. If orders be sent, checks should be made 
payable to the American Association of Botanical Gardens and Arboretums. 
EDIBLE WILD PLANTS OF EASTERN NORTH AMERICA by Merritt 
Lyndon Fernald and Alfred Charles Kinsey, pp. 422, 124 fig., 2.5 plates. Idle- 
wild Press, Cornwall-on- Hudson, New York. The Gray Herbarium of Harvard 
University announces this important publication. More than one thousand species 
of edible flowering plants and the more important edible ferns, mushrooms, sea- 
weeds and lichens which grow wild in North America north of Florida and east 
of the Great Plains are considered in this book. One hundred and twenty-five 
line drawings and twenty-five half tone plates aid materially in the identification 
of these edible plants and additional notes are given concerning their identifica- 
tion. Recipes for cooking and preserving the different types of vegetables and 
fruits are given. 
This is the most comprehensive and authoritative treatment of our edible wild 
plants ever prepared. It may be obtained either from the Idlewild Press, Corn- 
wall-on-Hudson, New York, or from the Gray Herbarium, Harvard University, 
Garden Street, Cambridge 38, Massachusetts. The price, post paid, is $3.00. 
Donald Wyman 

ARNOLDIA 
A continuation of the 
Bulletin of Popular Information 
of the Arnold Arboretum, Harvard University 
Volume 3 OCTOBER "29, 1943 Number 9 
WOODY PLANTS WITH YELLOW OR WHITE FRUITS 
GROWING IN THE ARNOLD ARBORETUM 
M OST of the berried plants in any landscape planting are those with red, 
blue or black fruits. Such is the case with barberries, roses and viburnums, 
three large groups of plants which are highly valued for their ornamental fruits. 
Shrubs and small trees with yellow or white fruits are just as ornamental especially 
when grown where their fruits can be viewed in contrast with plants having red 
or blue fruits. A few such plants, like the bittersweets and snowberries, are easily 
available from most nurseries, but some of the most striking, like the yellow 
fruiting viburnums, are very difficult to locate. 
The number of plants in each group is not large. Those with white fruits are 
so limited that plantsmen must depend almost entirely on a few of the shrubby 
dogwoods and the snowberries. These are commonly available from most nurse- 
ries. Those listed with an asterisk in this bulletin are the most ornamental, and 
nursery sources are given where some of these may be obtained. All are growing 
in the Arnold Arboretum. A few words about them might be of interest. 
Yellow Fruits 
I Unfortunately, the yellow fruiting Japanese barberry is not outstanding. The 
fruits are not borne in large numbers nor is the color a brilliant yellow. If it were 
possible to have a Japanese barberry with fruits a vivid, brilliant yellow, that 
plant would be of value. Such a barberry has not been developed as yet. 
The bittersweets have fruits the capsules of which are yellow. These split open, 
exposing the brilliant red aril, the fleshy part of the fruit. It should be remem- 
bered that all Cefastrus species have the sexes on separate plants and both stami- 
iiate and pistillate forms should be planted to insure fruiting. This is often eco- 
lomically done by planting a staminate plant in the same hole with a pistillate 
)lant, allowing the pistillate plant to grow at will but pruning the staminate plant 
o that only two or three stems will be allowed to grow. These will supply suffi- 
ient flowers to pollenize the flowers of a large pistillate plant. 
[ *5 ] 

The sea buckthorn, buffalo berry, yew, and the holly also have separate sexes 
and similar steps must be taken in order to insure their proper fruiting. 
The crab apples are noted for their brilliantly colored fruits, but, strangely 
enough, there are not many with completely yellow fruits, especially fruits which 
will remain colorful far into the winter. Most of the yellow crabapples have fruits 
which decay early. The Arnold crab is one example. The fruits are a fine yellow 
color, but they commence to decay even before the leaves' fall from the tree. 
Many seedlings of Mains robusta, baccata and prunifolia have yellow fruits, and 
future selections may result in establishing one that will retain its brilliant yel- 
low fruits far into the winter. 
The black currant, of course, serves as alternate host for the white pine blister 
rust and should not be grown in many sections of New England. The poison 
sumac is a native which naturally should never be used. 
The viburnums are really the best of all, for their brilliantly colored fruits stand 
out just as well as the red fruiting species. Both Viburnum Opulus xanthocarpum 
and V. Sargenti flavum have fruits a brilliant, golden yellow, the same size and 
shape as those of the species. The fruit clusters are so heavy that they often 
droop, as do those of the species, adding materially to their effective color. The 
fruits of V.dilatatum xanthocarpum are smaller, a lighter yellow color, and borne in 
rigid upright clusters. These three viburnums are truly outstanding and are well 
worth planting. The orange fruiting V. setigerum aurantiacum is also a good vari- 
ety, and is included in this list because it deserves being better known. 
White Fruits 
The common Tatarian dogwood and the native gray dogwood are perhaps the 
most commonly used white fruiting shrubs. The snowberries come a close second. 
Unfortunately, in some sections of the country several different diseases attack 
the fruits of the snowberries and they may prematurely turn black for this reason. 
The diseases are first noticed on the young foliage in late spring. Using a dormant 
spray of lime sulfur and burning all diseased canes is one method of controlling 
these diseases. Another method is to dust the twigs and berries during the late 
summer with copper-lime dust at about ten-day intervals until freezing weather 
arrives. All leaves and fallen fruits of diseased plants should be raked up in the 
fall and burned since the fungus may live over winter in these parts. 
The Japanese spurge produces few fruits but in older plantings the small py- 
ramidal fruit clusters are frequently conspicuous. The sumacs are both poisonous 
to the touch and should be avoided. The white fruiting blueberries last for such a 
short time that their fruits are practically useless from an ornamental standpoint. 
The fruits of Primus tomentosa leucocarpa are the same size as those of the spe- 
cies. Appearing in early summer, at a time when the leaves are fully developed, 
the fruits of this variety are sometimes so masked by the leaves that they do not 
stand out markedly. The unusual translucent fruits of Lonicera quin quel ocularis 
translucens are delicately unique among the ordinary berried shrubs, and for this 
reason they attract interest. 

Fruits Yellow 
( Figures denote nurseries from which available) 
Berberis Thunbergii xanthocarpa 
*Celastrus angulata 
*Celastrus flagellaris 
*Celastrus orbiculata (most) 
*Celastrus orbiculata major (6,7) 
*Celastrus scandens (most) 
^Cornus florida xanthocarpa (9) 
*Cornus mas flava 
^Crataegus punctata aurea 
Crataegus viridis padukensis (orange fruit) 
Daphne Mezereum alba 
Elaeagnus angustifolia 
^Hippophae rhamnoides (orange yellow) ( 1 , 
: Ilex verticillata ‘ Orange"’ 
fLonicera Morrowii xanthocarpa (?) 
‘Lonicera Ruprechtiana xanthocarpa (4) 
jpLonicera tatarica lutea (7) 
Malus arnoldiana (4,6) 
Malus baccata columnaris 
Malus “Bob White” 
Malus “Frau Luise Dittmann” 
Malus “Lady Northcliffe*’ 
Malus “Orange” 
Malus Scheideckeri 
Malus “Snowbank” (a) 
Malus spectabilis (yellowish) 
Mai us sublobata (4) 
Yellow Japanese Barberry 
Anglestem Bittersweet 
Korean Bittersweet 
Oriental Bittersweet 
American Bittersweet 
Yellowberry Flowering Dogwood 
Yellow Cornelian Cherry 
Yellow Dotted Hawthorn 
Yellow fruited February Daphne 
Russian Olive 
7) Common Sea Buckthorn 
Yellow Morrow Honeysuckle 
Yellow Manchurian Honeysuckle 
Yellow Tatarian Honeysuckle 
Arnold Crab Apple 
Columnar Siberian Crab Apple 
Scheidecker Crab Apple 
Chinese Flowering Crab Apple 
Yellow Autumn Crab Apple 
Note: Various unnamed seedlings, chiefly of M. baccata , M. prunifolia , 
and M. robusta also have bright yellow fruits. 
Chickasaw Plum 
Wild Myrobalan Plum 
David Peach 
Hortulan Plum 
Prunus angustifolia (red or yellow) 
Prunus cerasifera divaricata 
Prunus Davidiana (yellowish) 
Prunus hortulana (red or yellow) (a, 7) 
Prunus hortulana ‘Golden Beauty” 
(Prunus lanata (red or yellowish) 
, l) runus mandshurica 
Prunus maritima flava 
Prunus salicina (yellow or light red) 
’runus umbellata (red, yellow or dark purple) Flat woods Plum 
’runus virginiana xanthocarpa Yellow Choke Cherry 
Ihus verniciflua Japanese Lacquer Tree 
dibes nigrum xanthocarpum Yellow European Black Currant 
[- 17 ] 
Inch Plum 
Manchurian Apricot 
Yellow Beach Plum 
Japanese Plum 

*Rosa omeinsis chrysocarpa 
Sambucus nigra fructu-luteo 
*Shepherdia argentea xanthocarpa 
Sorbopyrus auricularis bulbiformis 
*Sorbus aucuparia xanthocarpa 
Taxus baccata lutea 
^Viburnum dilatatum xanthocarpuin (6,7 
* Viburnum Opulus xanthocarpum (7) 
* Viburnum Sargenti flavum 
* Viburnum setigerum aurantiacum (3,6,' 
Fruits 
*Cornus alba (most) 
Corn us asperifolia 
*Cornus racemosa (most) 
*Cornus stolonifera (most) 
^Daphne Genkwa ( 2,3 ) 
*Lonicera quinquelocularis (?) 
*Lonicera quinquelocularis translucens (7) 
Pachysandra terminalis 
*Prunus tomentosa leucocarpa 
Rhus radicans 
Rhus vernix 
Sambucus pubens leucocarpa 
*Symphoricarpos albus (most) 
*Svmphoricarpos albus laevigatus (most) 
*Symphoricarpos hesperius (8) 
*Symphoricarpos occidentalis (7) 
Symphoricarpos orbiculatus leucocarpus 
Vaccinium atrococcum leucococcum 
Vaccinium canadense leucocarpum 
Goldfruit Omei Rose 
Yellow European Elderberry 
Yellow Buffalo Berry 
Yellowberry European Mountain Ash 
Yellowfruited English Yew 
) Yellowberry Linden Viburnum 
Yellow European Cranberrybush 
Yellowfruit Sargent Cranberrybush 
r) Orangeberry Tea Viburnum 
Tatarian Dogwood 
Roughleaf Dogwood 
Gray Dogwood 
Red Osier 
Lilac Daphne 
Mistletoe Honej T suekle 
Whitefruit Mistletoe Honeysuckle 
Japanese Pachysandra 
Palefruit Manchu Cherry 
Poison Ivy 
Poison Sumac 
Pearl Elderberry 
Common Snowberry 
Garden Common Snowberry 
Washington Snowberry 
Western Snowberry 
White Coralberry 
White Downy Blueberry 
White Canada Blueberry 
Sources where the most ornamental may be obtained 
1. Arapahoe Acres Nursery, Littleton, Colorado 
2. Bobbink & Atkins Nurseries, East Rutherford, N.J. 
3. W. B. Clarke & Co., San Jose, California 
4. Cole Nursery Co., Painesville, Ohio 
5. Kelsey -Highlands Nurseries, East Boxford, Massachusetts 
6. Kingsville Nurseries, Inc., Kingsville, Maryland 
7. Henry Kohankie & Son, Painesville, Ohio 
8. Sheridan Nurseries, Ltd., Clarkson, Ontario, Canada 
9. Tingle Nursery Co., Pittsville, Maryland 
Donald Wyman 
[ 48 ] 

r:OV 29 1943 
J.IBRK&L 
ARNOLDIA 
A continuation of the 
Bulletin of Popular Information 
of the Arnold Arboretum, Harvard University 
Volume 3 NOVEMBER 19, 1943 Number 10 
SIMPLE KEY TO THE PINES 
(Native or available from nurseries in the United States) 
T HIS simple key is offered chiefly for the benefit of the amateur gardener who 
is frequently confronted with complicated keys which he finds to be too diffi- 
cult for his purposes. The key is based primarily on foliage characters which, in 
most cases, can be observed without the use of a hand lens. It should be clearly 
understood that any key based primarily on the length of the leaves (and this 
key is just that) is open to serious criticism because the length of the leaves of 
any plant will vary with the individual as well as with soil and climate variations, 
disease infestations, age and altitude at which the tree is growing. Other plant 
characters vary likewise. However, in order to assist the gardener who has an 
interest in pines, this key is offered in spite of such just criticism. It includes 
only those pines which one is likely to find in the woods or nurseries of this coun- 
try. A few native species have been omitted because they occur only in limited 
oreas, and many exotic species are omitted because they have not yet been widely 
jiistributed in cultivation. It goes without saying that the more species included 
n a key, the more complicated that key becomes. 
There are about 80 species of pines distributed throughout the northern hemi- 
sphere, 27 of which are growing in the Arnold Arboretum. This key includes all 
jut 5 of the species native to the United States, as well as 15 exotic ones avail- 
ible from nurseries, all in all 35 species of pines. 
! All measures of leaf length should be considered as approximate only. On one 
ndividual tree needles may vary in length from 2 inches to as high as 8 inches, 
out in the key the length given would be 4 to 6 inches, meaning that mature 
leedles- — not the young ones which are elongating, nor the ones on weak or on 
)ver-vigorous branches — are mostly within the 4 to 6 inch length. If this is 
•learly understood by those using this key, the key will undoubtedly prove help- 
ul in the identification of most of our commonly grown pines. 
[ 49 ] 

The key is designed to be used chiefly with living material, hence the color of 
the foliage and the general habit of the tree sometimes plays an important part. 
Occasionally, as in differentiating between Firms Strobus and P. monticola, the two 
species are so much alike that cone characters are used, but these are resorted to 
only when absolutely necessary, for many a tree which one would like to identify 
is not graced with cones at the time one wishes to identify it. 
This key can be greatly simplified for there are not many pines which are com- 
monly found in any one area in the United States. As an example, let us con- 
sider the five-needled pines. In “The Cultivated Conifers,” L.H. Bailey lists 15 
five-needled pine species of which 1 1 are growing in the Arnold Arboretum. 
Thirteen species and 4 varieties are listed in the following key. If this key were 
designed merely to identify the five-needled pines native to this country, the list 
would be reduced to 7 species. If the key were to be used in identifying pines 
native in the northeastern United States only, this part dealing with five-needled 
pines would include merely P. Strobus. 
Hardiness is given according to Zones in the Hardiness Map. Habitats are also 
given, because sometimes such information may prove helpful in assisting in plant 
identification. 
There is no excuse for avoiding a simple key such as this one, merely because 
of a lack of thorough botanical training. Such keys, when carefully made, are 
understandable, and if they are used with a full knowledge of their limitations, 
they will prove most helpful to the gardening public. Identifications made by the 
use of any key, and this one in particular, should not be considered final, but 
should be further checked against a complete description in some standard text, 
and available illustrations. 
SIMPLE KEY TO THE PINES 
Native or available in North America 
Needles in bundles of 2 to 5, rarely solitary, enclosed at the base by a decidu- 
ous or persistent sheath ...... Pinus 
1 . Needles 5 in a sheath 
a/bicaulis — White Bark P. 
aristata — Bristle-cone P. 
Ayacahuite — Mexican White P. 
Cembra — Swiss Stone P. 
Cem bra sibirica 
flexilis — Limber P. 
koraiensis — Korean P. 
Lambertiana — Sugar P. 
monticola — Western White P. 
parviflora — Japanese White P. 
pa rviflo ra gla uca 
Peuce — Balkan P. 
pumila — Japanese Stone P. 
Strobus — Eastern White P. 
Strobus fastigiata 
Strobus nana 
Torreyana — Torrey P. 
2. Needles usually less than 1^ inches long with smooth margin P. aristata 
(California to Colorado) Zone 5 
2. Needles usually 1^ to 2 inches long 
[50 ] 

3. Bark of trunk brown to creamy white, needles rigid and stout, margin 
smooth ....... P. albicaulis 
(British Columbia to California) Zone 3 
3. Bark of trunk black, needles more flexible 
4. Needles bluish green, often twisted, intensely white underneath, leaf 
margin finely serrulate, i.e., rough to the touch P. parviflora 
(japan) Zone 5 
4. Needles intensely bluish green . . P. parviflora glauca 
4. Needles light green, not twisted 
5. Mature twigs glabrous, needles smooth . . . P. flexilis 
(Alberta to California) Zone 4 
5. Mature twigs pubescent; leaf margin finely serrulate, i.e., rough to 
the touch 
6. Tree dense and upright in habit . . P. Cemba sibirica 
6. Tree more open ..... P. pumila 
(japan) Zone 3 
2. Needles mostly 2^ to 4^ inches long; leaf margin serrulate, i.e., rough to 
the touch 
3. Mature twigs glabrous 
4. Plant shrubby, not tree-like . . . . P. Strobus nana 
4. Branches upright, tree dense 
5. Needles stiff . . . . . . P. Peuce 
(Balkan Mts.) Zone 4 
5. Needles soft and flexible . . P. Strobus fastigiata 
4. Branches horizontal, tree more open 
5. Cones usually 2 to 4;§ inches long; twigs glabrous or only slightly 
pubescent ...... P. Strobus 
(Eastern U.S. and Canada) Zone 3 
5. Cones usually 4§ to 10 inches long; twigs pubescent when young 
(British Columbia to Idaho and California) Zone 5 P. monticola 
(These two species are difficult to tell apart with the naked eye, 
except that the habit of P. monticola is more narrow and dense and 
the needles stiffer than are those of P. Strobus.) 
3. Mature twigs pubescent 
4. Tree densely upright, pyramidal in habit . . P. Cembra 
(Alps of Europe) Zone 4 
4. Tree not as above, more open 
5. Needles lustrous, dark green . P. koraiensis 
(Japan, Korea) Zone 3 
5. Needles dull green 
6. Terminal bud blunt almost globular, cones 12 to 20 inches 
(Oregon to California) Zone 5 P. Lambertiana 

6. Terminal bud sharply pointed, definitely not globular, cones 4 to 
10 inches ...... P. monticola 
(British Columbia to Idaho and California) Zone 5 
2. Needles 4^ to 6 inches. Branchlets finely pubescent, needles bluish green 
(Mexico) Zone 9 ? P. Ayacahuite 
2. Needles 8 to 12 inches long . . . . P. Torreyana 
(Southwestern California) Zone 9 
Needles 3 to 4 in a sheath only occasionally 5; leaf margin smooth 
P. cembroides Parryana 
Parry Pinyon P. 
pomierosa — Ponderosa P. 
radial a — Monterey P. 
rigida — Pitch P. 
Sabiniana — Digger P. 
Taeda — Loblolly P. 
Zone 9 
1 . Needles 3 in a sheath 
attenuata — Knob-cone P. 
Burigeana- — Lace- bark P. 
canariensis — Canary P . 
Coulteri — Coulter P. 
palustris — Longleaf P. 
2 . Needles mostly 2 to 5 inches long 
3. Leaf sheaths deciduous, bark of older twigs smooth, bark of trunk flaky 
with white or yellow patches . P. Bungeana 
(China) Zone 4 
8. Leaf sheaths not deciduous, bark of older twigs very rough, bark of trunk 
dark brown to black 
4. Foliage dark green, cones usually 2 to 4 inches long P. rigida 
(Eastern U.S. and Canada) Zone 4 
4. Foliage bright or bluish green; cones 3 to 7 inches long 
5. Bark on upper part of trunk and branches smooth P. attenuata 
(Oregon to California) Zone 8 
5. Bark on upper part of trunk and branches rough P. radiata 
(S. California) Zone 8 
2. Needles mostly 5 to 10 inches long 
3. Winter buds resinous 
4. Twigs fragrant when broken; cones 3 to 6 inches; foliage dark green, 
branchlets orange brown . P. ponderosa 
(Eastern and Central U.S.) Zone 5 
4. Twigs not fragrant when broken; cones 9 to 14 inches; foliage bluisli 
green ....... P. Coulteri 
(California) Zone 8 
3. Winter buds not resinous 
4. Foliage bluish green; cones 3 to 6 inches . . P. Taeda 
(New Jersey to Florida and Texas) Zone 6 
4. Foliage dark green; cones 5 to 12 inches . P. Coulteri 
(California) Zone 8 
2. Needles 8 to 18 inches long 
[ 52 ] 

HARDI NESS MAP 

3. Foliage gray bluish green 
4. Needles slender, drooping . P. Sabiniana 
(California) Zone 6 
4. Needles stiff, erect ..... P. Coulteri 
(California) Zone 8 
3. Foliage green 
4. Needles mostly 8 to 10 inches long, light green and lustrous 
(Canary Islands) Zone 10 ? P. canariensis 
4. Needles mostly 12 inches or more long, dark green P. palustris 
(Southeastern U.S.) Zone 7 
1 . Needles 3 and 2 in a sheath 
caribaea — Slash P. 
cembroides — Mexican Pinyon P. 
echinata — Shortleaf P. 
ponderosa scopulorum — Rocky Mountain Ponderosa P. 
tabulaeformis — Chinese P. 
2. Needles less than 2 inches long . . . P. cembroides 
(Southern California and Arizona) Zone 9 
2. Needles more than 2 inches long 
3. One year twigs greenish to purplish, covered with glaucous bloom 
(Eastern U.S.) Zone 5 P. echinata 
3. One year twigs yellow brown to brownish 
4. Terminal bud very resinous . P. ponderosa scopulorum 
(Rocky Mountain Region) Zone 4 
4. Terminal bud not resinous or only slightly so 
5. Needles 2 to 7 inches long; cones 1^ to 2 inches long 
(China) Zone 5 P. tubulaeformis 
5. Needles 8 to 12 inches long; cones 3 to 6^ inches long P. caribaea 
(Southeastern U.S., Bahamas, Honduras) Zone 8 
1 . Needles 2 in a sheath 
Banksiana — Jack P. 
densiflora — Japanese Red P. 
d en si flora ocul us-d raconis 
densiflora umbraculifera 
echinata — Shortleaf P. 
Mugo — Swiss Mountain P. 
Mugo compacta 
Mugo pumilio 
nigra austriaca — Austrian P. 
nigra Poiretiana 
2. Needles § to 3 inches long 
3. Foliage with each needle marked with a yellow band 
P. densiflora oculus-draconis 
Pinaster — Cluster P. 
pungens — Table Mountain P. 
resinosa — Red P. 
sylvestris — Scotch P. 
sylvestris aurea 
sylvestris ri gen sis 
sylvestris Watereri 
tabulaeformis — Chinese P. 
Thunbergn— Japanese Black P. 
virginiana — Virginia P. 
[ 54 ] 

P. sylvestris and vars. 
3 . Foliage bluish green, bark of upper trunk red 
(Europe) Zone 2 
4 . Young foliage at first yellow, changing later to bluish green 
P. sylvestris aurea 
4 . Bark very red, trunk tall and straight P. sylvestris rigensis 
4. Habit low, dense, pyramidal, needles steel blue P. sylvestris Watereri 
3. Foliage green 
4. Plant usually shrubby, with several main branches from the base 
5. Needles § to 2 inches long, bark black P. Mugo and vars. 
(Central Europe) Zone 2 
6 . Dense almost globose shape . . P. Mugo compacta 
6 . Shrubby, upright habit . P. Mugo pumilio 
5. Needles 3 to 5 inches, bark red to reddish P.densiflora umbraculifera 
4. Plant a tree with a central leader 
5. Needles mostly one inch long . . P. Banksiana 
(Northeastern U.S. and Eastern Canada) Zone 2 
5. Needles I 4 to 3 inches long 
6 . Branchlets usually with glaucous bloom, often greenish to purplish 
or yellowish 
7. Foliage bluish green, cones usually not persistent, bark of upper 
trunk red ; leaves flexible . . P. densiflora 
(Japan) Zone 4 
7 . Foliage bright green, cones persistent, bark of upper trunk black ; 
leaves stiff’ . . . P. virginiana 
(Eastern U.S.) Zone 4 
6 . Branchlets without glaucous bloom, orange to yellow 
7. Vigorous shoots often with more than one whorl of branches on 
the current year’s growth P. pungens 
(Southeastern U.S.) Zone 5 
7. Vigorous shoots with only one whorl of branches on the current 
year’s growth 
8 . Winter buds white or whitish to light yellow P. Thunbergii 
(japan) Zone 4 
8 . Winter buds dark brown . . . P. tabulaeformis 
(China) Zone 5 
2 . Needles 3 to 8 inches long 
3. Winter buds resinous 
4. Needles slender and flexible not breaking when bent P. resinosa 
(Northeastern U.S. and Eastern Canada) Zone 2 
4. Needles stout and stiff breaking when bent P. nigra austriaca 
(Central Europe) Zone 4 
5. Branches more ascending P. nigra Poiretiana 
3. Winter buds not resinous (or only slightly so in P. tabulaeformis) 
[ 5.5 ] 

4. Buds stout, up to one inch long; branchlets bright reddish brown 
(Portugal to Greece) Zone 8 P. Pinaster 
4. Buds less than i inch long 
5. Bark of upper trunk red . . . P. densiflora 
(japan) Zone 4 
5. Bark of upper trunk black 
6. One year twigs with glaucous bloom, green to purplish P. echinata 
(Eastern U.S.) Zone 5 
6. One year twigs without glaucous bloom, yellow to brown 
7. Winter buds dark reddish brown . P. tabulaeformis 
(China) Zone 5 
7. Winter buds light yellow to white or whitish P. Thunbergii 
(japan) Zone 4 
Donald Wyman 
Note: The demand for copies of “Crab Apples For America” has been so 
great that a second printing has been ordered. Copies may be obtained by writ- 
ing the Arnold Arboretum, Jamaica Plain, Mass, and enclosing a check for $1.00 
made out to the American Association of Botanical Gardens and Arboretums. 

ARNOLDIA 
A continuation of the 
Bulletin of Popular Information 
of the Arnold Arboretum, Harvard University 
Volume 3 DECEMBER 17, 1943 Number 11 
SIMPLE FOLIAGE KEY TO THE HEMLOCKS AND SPRUCES 
T HIS is a group of narrow leaved evergreens which is extremely difficult to 
identify from foliage characters alone. Especially is this true of the spruces. 
One of the reasons they are difficult is because of the fact that the needles soon 
fall off when they are dry. The key which follows is prepared solely for the de- 
termination of material which is fresh. It cannot be used with dead material. 
Such a key has its good points and its bad points — good because the obvious 
characteristics such as color of foliage and twigs are used and it can be used in 
the field without the use of a lens (in most cases), bad because the key is only 
isable for the period of a few days after the branches have been taken from the 
living tree. 
All that is said in Arnoldia, Volume 3, No. 10, 1943, describing the Key to the 
Pines, is also applicable to this key to the spruces and hemlocks. The key is 
)ffered for the garden enthusiast who is not a trained botanist, but the key should 
lot be used as a means of final identification, standard texts and illustrations should 
ie consulted. 
Most of the characters used can be observed with the naked eye. Since many 
nurserymen grow the spruce species from seed, there is the opportunity for hy- 
>rids to creep into the trade and obviously these always prove troublesome in 
iny key. 
It is interesting to note that there are only 7 species of spruce native to North 
\merica, and all are included in this key. There are about 22 species available in 
he trade, all of which are included in the key, as well as 10 varieties in addition. 
There are about 26 varieties of Pica Abies offered by various nurseries, and the 
lifferences among these are frequently so slight, especially in the younger stages 
>f plant development, that it is impossible to make a satisfactory key for them. 
Consequently, it has only been possible to list the dwarf varieties of P. Abies as 
. group. 
[ 57 ] 

Of the hemlocks, four species are native and these are included in the key of 
six species. At least 15 varieties of Tsuga canadensis are offered in the trade and 
probably many more. It was impossible to make a foliage key for these because 
in many cases their differentiation depends on their shape alone. 
As in the Key to the Pines, habitats are given for all species and Hardiness 
Zones refer to the Hardiness Map, Arnoldia, Vol. 3, No. 10, 1943, p. 53. 
FOLIAGE KEY TO THE HEMLOCKS AND SPRUCES 
(Native or available in North America) 
Needles borne singly, leaf bases persistent . . . Picea and Tsuga 
1 . Needles narrowed at base to form distinct petioles Tsuga species 
This character must be clearly interpreted. 
Sometimes when the needle of a spruce is 
pulled off, a small portion of the twig bark 
also comes off, looking like a petiole unless 
observed with a lens. The needles of all 
spruces are without petioles, their leaf-blades 
being attached directly to the twig. 
Figure 1 . Needle of hemlock (a) with pet- 
iole and spruce (b) without petiole. 
a b 
canadensis — Canada Hemlock heterophylla — Western H. 
caroliniana — Carolina H. Mertensiana — Mountain H. 
divers'ifolia Japanese H. Sieboldii — Siebold H. 
2. Needles with white lines on under surface only, cones less than 2 inches 
long 
3. Needles noticeably blunt and notched at tip 
4. One year branchlets pubescent . . T. diversifolia 
(Japan) Zone 5 
4. One year branchlets glabrous T. Sieboldii 
(Japan) Zone 5 
3. Needles not noticeably notched at end but rounded 
Figure 2. a. Tsuga canadensis. The very fine 
serrulate margin can only be 
seen with a lens. 
b. Tsuga Sieboldii 
c. Tsuga caroliniana 
[ 58 ] 

4. Many of the needles on vigorous one year shoots wider at base than 
at the tip; i.e., gradually tapering from base to tip; needles mostly 
two ranked, in one plane, and with a very fine serrulate margin (when 
examined with a lens) ; cones § inch or less in length T. canadensis 
(Nova Scotia and eastern U.S.) Zone 4 
4. Majority of needles on vigorous one year shoots not tapering but about 
as wide at base as at tip ; needles in several planes about twig; needle 
margin of T. caroliniana entire and T. heterophylla is serrulate (when 
examined with a lens). Cones longer than f inch 
5 . One year twigs orange brown, cones 1 to l| inches long 
(Southeastern U.S.) Zone 4 T. caroliniana 
5. One year twigs pale yellowish brown; cones 4 to 1 inch long 
(Alaska to Idaho and California) Zone 6 T. heterophylla 
2. Needles with white lines on upper and lower surfaces, cones 2 inches or 
more in length . . T. Mertensiana 
(Alaska to Idaho and California) Zone 5 
1 . Needles without distinct petioles 
Abies — Norway Spruce 
Abies vars . — some 26 varieties avail- 
able in the trade 
asperata — Dragon S. 
bicolor — Alcock S. 
Breweriana — Brewer S. 
Engelmanni — Engelmann S. 
glauca — White S. 
glauca albertiana — Alberta S. 
glauca conica — Dwarf Alberta S. 
glauca densata — Black Hills S. 
Gleknii — Sakhalin S. 
jezoensis — Yeddo S. 
Koyamai — Koyama S. 
mariana — Black S. 
mariana Doumetii — Doumet S. 
Picea species 
Omorika — Serbian S. 
orient alis — Oriental S. 
orientalis aurea — Bronze Oriental S. 
polita — Tiger tail S. 
pun gens — Colorada S. 
pungens argentea — Silver S. 
pun gens Bakeri — Baker S. 
pungens glauca — Blue Colorado S. 
pungens Kosteriana — Koster S. 
pungens Moerheimii — Moerheim S. 
purpurea — Purple Cone S. 
rubens — Red S. 
Schrenkiana — Schrenk S. 
sitchensis — Sitka S. 
Smit hiana — Himalayan S. 
Wilsonii — Wilson S. 
obovata — Siberian S. 
2. Needles on current year’s growth mostly at right angles to twig; also see 
Fig. 5, p. 61. (Note: In no specimen are all the needles exactly at right 
angles to the twig. Some needles always point towards the end of the 
twig hence making an angle less than a right angle. However, the plants 
in the group with needles at right angles should have more than fifty per 
cent of their needles at right angles to the twig. In case of reasonable 
doubt, certain plants can be located again under the second No. 2 — 
^Needles mostly at an angle considerably less than a right angle.”) 
[ 59 ] 

Figure 3. Tip of one year shoot 
of Picea pungens showing a majority 
of the needles nearly at right angles 
to the twig. 
3. Needles inch long or less 
4 . Needles showing intense white lines when observed from tip looking 
towards base of branch ; branchlets pubescent 
5. Plant a tree, loose and open in habit . P. mariana 
(Labrador to Alaska; Wisconsin and Michigan) Zone c 2 
5. Plant not so tall, dense conical habit P. mariana Doumetii 
4 . Needles not showing intense white lines, plant a low dense pyramid 
of tightly compact light green foliage ; branchlets glabrous 
P. glauca conica 
3. Needles mostly more than ^ inch long 
4. Terminal bud lustrous, dark brown, prominent, about 4 inch long; 
its tight fitting scales remaining snugly tight fitting and blackish at 
base of branchlets for several years . . . . P. polita 
(Japan) Zone 5 
Figure 4. End bud and base of one 
year shoot of Picea polita (a) and Picea 
Abies (b) showing the tight fitting 
scales on bud and shoot base of P. polita 
as compared with those of P. Abies. 
4. Terminal bud not lustrous nor as prominent, light brown. The scales, 
if they remain at the base of the current year’s branchlets are curled 
and indistinct, not snugly tight fitting 
5. Foliage of one year twigs definitely blue P. pungens glauca 
P. pungens argentea 
P. pungens Moerheimii 
[00] 

The only way to tell these three apart is to determine the degree 
of blue color. P. pungens glauca is the least blue, P. pun gen a ar gen- 
tea the typical Roster's Spruce” of the trade is next, and P. 
pungens Moerheimii is the deepest blue. 
Note: (Visualize the blue of P. pungens argentea [the typical “Ros- 
ter’s Spruce” of the trade, sometimes incorrectly named Kosteri 
or Kosteri ana . ] and the green of the Norway spruce. These are the 
two sharp color divisions. Plants with foliage a color between these 
two extremes come under the second No. 5 — “Foliage bluish to 
grayish green” 
5. Foliage bluish to grayish green 
6. Needles rigid, extremely sharp to the touch, one year shoots 
strong and vigorous often 6 to 10 inches long 
7. Needles frequently curved P. asperata 
(West China) Zone 5 
7. Majority of needles straight P. pungens 
(Wyoming to New Mexico) Zone 2 
6. Needles not so rigid and sharp to the touch, one year shoots not 
so vigorous 
7. One year twigs greenish gray . . P. Wilsonii 
(Central and West China) Zone 5 
7. One year twigs yellowish to orange brown P. glauca 
(Canada and northern U.S) Zone 2 
5. Foliage uniformly green. Usually most of the needles of this spe- 
cies are not at right angles to the twigs but sometimes on very 
vigorous shoots they are . . . P. Abies 
(North and Central Europe, naturalized in eastern U.S.) Zone 2 
2. Needles on current year’s growth mostly at an angle considerably less 
than a right angle with the twig; i.e., needles pointing towards the tip 
of the twig. Also see Fig. 3, p. 60. 
Figure 5. Tip of one year shoot of 
Picea Enge/manni showing a majority 
of the needles at less than right angles 
to the twig. 
3. 
Foliage of current year’s shoots uniformly blue. (Note: Visualize the 
blue of P. pungens argentea [the typical “Foster’s Spruce” of the trade] 
[61 ] 

and the green of the Norway spruce. These are the two sharp color 
divisions. Plants with foliage a color between these two extremes come 
under the second No. 3 — “Foliage bluish to grayish.”) 
4. One year twigs densely pubescent, noticeable without a lens 
(British Columbia to Arizona) Zone 2 P. Engelmanni 
4. One year twigs glabrous 
5. Plant with rigid, horizontal branches . P. pungens Bakeri 
5. Plant with pendulous branchlets . . P. pungens Kosteriana 
(Not to be confused with the Silver spruce, P. pungens argenten, 
which does not have pendulous branchlets) 
Foliage of current year’s growth bluish to grayish or whitish ; especially 
when viewed from tip of branch, looking toward base of branch ; green 
when viewed from above the branch 
4. Needles § inch or less in length 
5. One year twigs greenish gray P. purpurea 
(West China) Zone 5 
5. One year twigs yellowish to brown 
6. Needles flat in cross section 
Figure 6. Cross section of needle of Picea 
Omorika (below) and Picea g/auca (above). 
7. Winter buds resinous 
8. Branchlets glabrous and horizontal, foliage intensely white 
when viewed from underneath the branch 
9. Needles pungent, 2 to 1 inch long P. sitchensis 
(Alaska to California) Zone 6 
9. Needles not pungent, 2 to 4 inch long P. jezoensis 
(Manchuria and Japan) Zone 4 
8. Branchlets pubescent, usually markedly pendulous ; foliage 
not intensely white when viewed from beneath 
(Oregon to northern California) Zone 5 P. Breweriana 
7. Winter buds not resinous; branchlets pubescent P. Omorika 
(Southeastern Europe) Zone 4 
6. Needles angular in cross section, usually 4-sided 
7. Two and three year old twigs black on upper side of branch 
at least, giving a dark appearance to the tree ; needles sharp: 
branchlets pubescent P. mariana 
(Labrador to Alaska, Wisconsin to Michigan) Zone 2 

7. Two year twigs usually light brown; branchlets glabrous, 
needles blunt 
8 . Tree slow growing, dense and compact P. glauca densata 
8 . Tree more open in habit . . . P. glauca 
(Canada and northern U.S.) Zone 2 
P. glauca albertiana 
(Alaska and British Columbia to Montana) Zone c 2 
(Note : It is difficult to tell these two apart with the naked 
eye. P. glauca albertiana is considered a geographical va- 
riety of the species.) 
One year twigs definitely a red brown 
6 . Cones 24 to 4§ inches long 
P. bicolor 
(Japan) Zone 4 
6 . Cones 2 to 3 inches long 
P. Glehnii 
(japan) Zone 3 
(Here is a case where differentiation between these two species 
without a lens and without fruit is very difficult; the differences 
are largely those of degree. The white markings on the upper 
surface of the needles of P. bicolor are more intense, whereas the 
pubescence of the branchlets and the dark green color of the 
branchlets of P. Gleknii is more marked.) 
4. Needles more than § inch long 
5. Needles flat in cross section; see Fig. 6 , p. 62. 
6 . Branchlets glabrous ; foliage intensely white when observed from 
underneath branch . P. sitchensis 
(Alaska to California) Zone 6 
6 . Branchlets pubescent ; usually markedly pendulous ; foliage not 
intensely white when observed from underneath branch 
(Oregon to northern California) Zone 5 P. Breweriana 
5. Needles angular in cross section, usually 4-sided 
6 . Winter buds resinous . . P. Smithiana 
(Himalayas) Zone 6 
6 . Winter buds not resinous . P. Schrenkiana 
(Central Asia) Zone 5 
3. Foliage uniformly green 
4. The majority of the needles ^ inch or less in length 
5. Needles flattened against branchlets; a markedly uniform dark 
glossy green above and below P. orientalis 
(Caucasus and Asia Minor) Zone 4 
5. Needles not flattened against branchlets except in some P. Abies 
varieties which are dwarf shrubs and not trees ; nor a marked uni- 
form glossy green above and below except sometimes in P. rubens 
[ 63 ] 

6. Plants usually low, dense, dwarf shrubs P. Abies varieties 
(Note: Some 26 dwarf varieties are offered in the trade.) 
6. Plants not low, dense, dwarf shrubs, but trees 
7. One year twigs yellowish, foliage gray green P. glauca 
(Canada and northern U.S.) Zone 2 
7. One year twigs reddish brown; foliage green 
8. Needles only slightly glossy, branchlets pubescent 
(Nova Scotia to North Carolina) Zone 2 P. rubens 
8. Needles not glossy, branchlets glabrous P. koyamai 
(Japan and Korea) Zone 4 
4. The majority of the needles at least ^ inch and usually approaching 
§ inch in length 
5. Foliage dark green, branchlets usually orange 
6. Terminal bud lustrous, dark brown, prominent, about \ inch 
long ; its tight fitting scales remaining snugly tight fitting and 
blackish at base of branchlets for several years ; foliage decid- 
edly harsh to the touch ; see Fig. 4, p. 60 P. polita 
(Japan) Zone 5 
6. Terminal bud not lustrous. The scales if they remain at the base 
of the current year’s branchlets are curled and indistinct, not 
snugly tight fitting; foliage not harsh to the touch; see Fig. 4, 
p. 60 P. Abies 
(North and Central Europe, escaped in U.S.) Zone 2 
5. Foliage grayish green, one year twigs yellowish 
6. Needles usually rigidly upright on the upper side of the branch- 
lets ; needles dense, even on four year old branchlets ; tree open 
in habit . . P. glauca 
(Canada and northern U.S.) Zone 2 
Figure 7. Side view of shoot 
of Picea obovata (above) and Picea 
glauca (below) showing the dif- 
ference in the way the needles 
are borne on the twig. 
6. Needles usually appressed or held closely along the upper side 
of the branch, not upright; needles sparsely borne; tree dense 
and conical in habit P. obovata 
(Northern Europe to Kamchatka and Manchuria) Zone 2 
. Foliage bronze golden, at least when the needles first appear in spring. 
The majority of the needles less than ^ inch long ; plant a tree 
P. orientalis aurea 
Donald Wyman 
[ 64 ] 

ARNOLDIA 
A continuation of the 
Bulletin of Popular Information 
of the Arnold Arboretum, Harvard University 
Volume 3 
DECEMBER 31, 1943 
Number 
A SIMPLE FOLIAGE KEY TO THE FIRS 
HIS simple foliage key to the firs is the third and last in this series of keys 
A to the narrow-leaved evergreens, and all statements made concerning the 
other two (Simple Key to the Pines; Arnoldia, 3: No. 10, 1943; and a Simple 
Foliage Key to the Hemlocks and Spruces; Arnoldia, 3: No. 11, 1943) apply 
to this key to the firs. 
The firs are perhaps the most difficult of the four groups of plants to tell apart 
because their needles vary considerably in size and shape, and the color of the 
twigs and the amount of pubescence on them also varies. 
There are ten fir species native to this country, all of which are included in 
the following key, in addition to fifteen exotic species and six varieties. All of 
these are either native or being grown commercially at some place in the United 
States. As with the pines and spruces, many more firs are being grown in botan- 
ical gardens and arboretums in this country but their cultivation is limited to such 
an extent that they are not available at this time to the plant buying public in 
sufficient quantity to warrant their inclusion in this key. 
The Zones refer to the Hardiness Map, Arnoldia, 3: No. 10, 1943, p. 53. The 
habitats are given for all species appearing in the key, for such information is 
often helpful in identifying these plants in the field. 
Note: The three simple foliage keys to the evergreens given in this and the two 
preceeding numbers of Arnoldia should materially aid the gardening enthusiast or 
woodsman in his associations with this valued group of plants. The keys cover prac- 
tically all the pines, hemlocks, spruces and firs native in large areas in this country 
or grown in quantity in our commercial nurseries. Actually, 104 evergreen trees 
are included in these keys, of which 41 species are native to this country. This 
is about all the evergreens in these groups which one would normally find in the 
woods, parks and gardens of the United States. It is hoped that these keys may 
stimulate an interest in the names and relationships of these conifers. They were 
planned to be used with living plants. Use them and learn to know your evergreens ! 

SIMPLE FOLIAGE KEY TO THE FIRS 
Native or available in North America 
Leaves single, leaving a circular scar when falling ; without persistent prominent 
leaf bases on the twigs ..... Abies, Pseudotsuga 
Figure 8. a. Twig of fir showing the smooth 
twig surface when the leaves have 
fallen 
b. Twig of spruce, showing the small 
leaf bases (making a rough twig 
surface) which remain after the 
leaves have fallen 
1 . End bud sharply pointed, long and narrow, with many scales, not resinous; 
fruit a pendulous cone, needles spreading radially on all sides of twig 
Pseudotsuga taxifolia — Dou glas- Fir 
Pseudotsuga taxifolia glauca 
Figure 9. a. Terminal bud of fir 
b. Terminal bud of Pseudotsuga 
taxifolia showing its many 
scales and long pointed char- 
acter distinctly different from 
the buds of any fir 
2. Foliage green ..... Pseudotsuga taxifolia 
(British Columbia to western Texas) Zone 6 
Z. Foliage bluish green .... P. taxifolia glauca 
(Rocky Mountains) Zone 4 
1 . End bud not long and narrow and sharply pointed, mostly resinous; fruit 
upright, needles of most species (except A. Pinsapa and A. koreana ) not 
spreading radially on all sides of twig (see Figs. 9 and 10) Abies species 
alba — Silver Fir 
alba pyramidalis 
amabilis — Cascades F. 
balsamea — Balsam F. 
cephalonica — Greek F. 
chensiensis — Shensi F. 
cilicica — Cilician F. 
con color — Colorado F. 
concolor violacea 
Jirma — Momi F. 
Fraseri — Southern Balsam F. 
Fraseri prostrata 
grand is — Giant F. 
holophylla — Needle F. 
homolepis — Nikko F. 
koreana — Korean F. 
[ 60 ] 

lasiocarpn — Rocky Mountain F. 
lasiocarpa arizonica 
magnified — Red F. 
Mariesii — Maries F. 
Nordmanniana — N ord man n F . 
proceed g/dued 
re/igio.m — Sacred F. 
sacha/inensis — Saghal i n F . 
sibiricd — -Siberian F. 
spectabilis — H imalayan F. 
Pinsapo — Spanish F. Veitchii — Veitch F. 
Pinsapo gldiicd venusta — Bristle-cone F. 
proceed (formerly A. nobilis ) — Noble F. 
2. Needles mostly § inch or less in length 
3. Needles spreading radially on all sides of twig 
Figure 10 . a. Abies koredna showing 
needles spreading radially 
b. Abies alba showing needles 
distinctly 2-ranked 
c. Abies Nordmanniana show- 
ing needles appearing on 
sides and from upper sur- 
face of twig 
4. Needles intensely white beneath, usually blunt and rounded at the 
tip ....... A. koreana 
(Korea) Zone 5 
4. Needles greenish to greenish white beneath usually pointed at the 
tip ...... A. Pinsapo 
(Spain) Zone 6 
4. Needles glaucous or bluish ... A. Pinsapo glauca 
3. Needles not radially distributed; apparently more or less 2-ranked, 
that is with needles appearing on the two sides of the twig and fre- 
quently on the upper surface as well (see Fig. 10) 
4. Needles lustrous green above, white or whitish beneath : stomate 
lines present on under surface only 
5. Needles, especially on 2 year old twigs, directed toward tip of 
branch (see Fig. 12) . A. Mariesii 
(Japan) Zone 5 
5 . Needles, especially on 2 year old twigs, more or less at right angles 
to the twigs (see Fig. 12) 
b. Plant a tree ..... A. balsamea 
(Labrador to W. Virginia and Iowa) Zone 3 
A. Fraseri 
(Allegheny Mts., W. Virginia and Tennessee) Zone 4 
(These two are closely related and difficult to tell apart without 
[ 07 ] 

cones or without a lens. The under surface of the needles of 
A. Fraseri has 8 to 12 lines of stomates in each white band, 
while that of A. halsamea has only 4 to 8 lines in each white band) 
6. Plant a prostrate shrub A. Fraseri prostrata 
4. Needles gray green above and below, due to the fact that stomate 
lines (seen with a lens) are on both upper and lower needle surfaces 
5. One year twigs ashy gray 
b. Bark or trunk gray . . . A. lasiocarpa 
(Alaska to New Mexico) Zone 3 
6. Bark of trunk creamy white and corky A. lasiocarpa arizonica 
5. One year twigs rusty brown 
b. Foliage bluish green . .A. procera (A. n obi Us ) 
(Washington to California) Zone 5 
6. Foliage glaucous or bluish . . A. procera glauca 
Needles more than § inch in length 
3. Needles green and lustrous above; no lines of stomates on upper sur- 
face of needles (when observed with a lens) 
4. Needles definitely pointed at tip 
Figure 11. a. Tip of needle of A. holophylla 
b. Tip of needle of young A.Jirmn 
c. Tip of needle of A. cephalonica 
d. e, f. Rounded and slightly notched 
needles commonly found on most firs. 
When any of these types make up a 
majority of the needles of a specimen, 
the needles are considered to be blunt 
as far as this key is concerned 
(Note: — For the purposes of this key needles similar to those of a, 
b and c are considered pointed or sharp. This can usually be felt by 
gently squeezing the ends of the needles. Those similar to d, e and 
f are considered blunt. It should be understood that needles vary 
greatly and some trees will have differently shaped needles, often on 
the same branch. Typical needles should be considered to be those 
appearing on the specimen in the greatest number) 
5. Ma jority of needles especially on 2 year old twigs at right angles 
to the twigs (see Fig. 12) 
6. Branchlets glabrous ; vigorous shoots have needles with only one 
point 
7. Twigs deeply grooved (see Fig. 12) 
(Japan) Zone 4 
7. Twigs not deeply grooved 
[08 ] 
A. homolepis 

8. White lines clearly visible on the lower surface of the 
needles; needles frequently produced on all sides of twig 
(G reece) Zone 5 A. cephalonica 
8. White lines only faintly visible on the lower surface of the 
needles; needles often curved and pointing directly up- 
ward, not appearing radially arranged A. holophylla 
(Manchuria, Korea) Zone 5 
b. Branchlets slightly pubescent; vigorous young shoots may have 
needles with two sharp points (see Fig. 1 I ) A. firma 
(Japan) Zone b 
5. Majority of needles not at right angles to twig (see Fig. 12) 
6. Needles less than 1^ inches long 
7. One year twigs glabrous 
(Manchuria, Korea) Zone 5 
7. One year twigs pubescent 
(Mexico) Zone 9-10? 
6. Needles 1^ to 2^ inches long . 
(California) Zone 8 
4. Majority of needles blunt and rounded at tip or slightly notched at 
the tip (see Fig. 1 1) 
5. Needles, especially on 2 year old twigs, mostly at right angles to 
the twigs 
Figure 12. a. Needles most- 
ly at right angles to 
twigs as in A.homolepis , 
also showing longitudi- 
nal lines or grooves in 
twig. 
b. Needles mostly direct- 
ed towards the tip of 
twigs as in A. Nordman- 
niana 
A. holophylla 
A. religiosa 
A. venusta 
6. Branchlets glabrous 
7. Foliage intensely white beneath; twigs deeply grooved (see 
Fig. 12) .A. homolepis 
(Japan) Zone 4 
7. Foliage green beneath ; twigs not deeply grooved 
(Central China) Zone 6 A. chensiensis 
6. Branchlets pubescent 
7. Branchlets slightly pubescent, one year twigs often have faint 
grooves; needles on vigorous shoots frequently pointed, 
needles up to 1^ inches long . . .A. firma 
(Japan) Zone b 
[ 09 ] 

7. Branchlets densely pubescent, needles rarely more than 1 inch 
in length 
8. Plant a tree .... A. balsamea 
(Labrador to W. Virginia and Iowa) Zone 3 
A. Fraseri 
(Allegheny Mts., W. Virginia and Tennessee) Zone 4 
(These two are closely related and difficult to tell apart with- 
out cones or without a lens. The under surface of the needles 
of A. Fraseri has 8 to 12 lines of stomates in each white band, 
while that of A. balsamea has only 4 to 8 lines in each white 
band) 
8. Plant a prostrate shrub . A. Fraseri prostrata 
5. Majority of needles not at right angles but pointing toward the 
tips of the twigs (see Fig. 12) 
6. Lower side of one year twigs olive green A. grandis 
(Vancouver to California and Montana) Zone 6 
6. One year twigs not olive green 
7. Foliage grayish white beneath: needles 1/24 to 1/16 inch in 
width 
(Note :• — This is a difficult measurement to make but the point 
is that the needles of the following two firs are narrower than 
those of most other species) 
8. Needles dark green A. sachalinensis 
(Japan, Kurile Isis.) Zone 2 
8. Needles light green ... A. sibirica 
(Northern Russia to Kamchatka, Turkestan and Manchuria) Zone 2 
(These two are difficult to tell apart without a lens. The under- 
surface of the needles of A. sachalinensis has 7 to 8 lines of 
stomates in each white band while that of A. sibirica has only 
4 to 5 lines in each white band) 
7. Foliage of one year shoots intensely white beneath ; needles 
l/l2 inch or more in width 
8. Winter buds resinous 
9. Needles mostly more than 1 inch long (l to 2j inches) 
twigs usually grooved . . A. spectabilis 
(Himalayas) Zone 7 
9. Needles mostly less than 1 inch long; twigs not grooved 
10. Branchlets gray pubescent A. amabilis 
(British Columbia to Oregon) Zone 5 
10. Branchlets brown pubescent A. Veitchii 
(Japan) Zone 3 
8. Winter buds not resinous 
[ 70 ] 

9. Leaves closely arranged in two ranks like teeth in a 
comb (see fig. 10) 
10. Tree pyramidal in habit .A. alba 
(Mountains of Central and Southern Europe) Zone 4 
10. Tree columnar in habit A. alba pyramidalis 
9. Leaves not in two closely arranged ranks 
10. Needles of one year twigs very white beneath, the 
upper ones directed forward and closely appressed 
to the twigs A. Nordmanniana 
(Caucasus Mts. and Asia Minor) Zone 5 
10. Needles of one year twigs merely greenish white be- 
neath, more or less spreading and with a V-shaped 
depression above, not closely appressed to the twigs 
(Asia Minor, Syria) Zone 5 A. cilicica 
(These two are difficult to tell apart without the cones. 
The Nordmann Fir is by far the more common of the 
two in this country) 
3. Foliage dull grayish or bluish green above and below because there 
are stomatiferous lines on both upper and lower surfaces of the needles 
(These can be seen with a lens) 
4. Needles flat in cross section (as in Picea Omorika. Arnoldia 3: No. 
11, 1943, Fig. 6, p. 62) 
5. One year twigs glabrous 
6. Foliage bluish green .... A. concolor 
(Colorado to California and New Mexico) Zone 4 
6. Foliage a bluish white . .A. concolor violacea 
5. One year twigs pubescent 
6. Twigs ashy gray 
7. Bark of trunk gray .... A. lasiocarpa 
(Alaska to New Mexico) Zone 3 
7. Bark of trunk creamy white and corky A. lasiocarpa arizonica 
6. Twigs rusty brown 
7. Foliage bluish green A. procera (A. nobilis ) 
(Washington to California) Zone 5 
7. Foliage glaucous or bluish . A. procera glauca 
4. Needles, at least some of them, quadrangular in cross section, simi- 
lar to the cross section of those of Picea glauca (see Arnoldia 3 : No. 
11, 1943, Fig. 6, p. 62) . . .A. magnifica 
Donald Wyman 


INDEX TO VOLUME III 
Illustrations are in bold face type 
Abies, 66 
— alba. Fig. 10 (c), 67, 71 
w~' — pyramidalis, 71 
— amabilis, 70 
— balsamea, 67, 70 
— cephalonica, Fig. 11 (c), 68, 69 
— chensiensis, 69 
— cilieica, 7 1 
— concolor, 7 1 
violacea, 71 
— firma, 69 
E , tip of needle, Fig. 11 (b), 68 
— Fraseri, 67, 70 
prostrata, 68, 70 
— grandis, 70 
— holophylla, 69 
tip of needle, Fig. 11 (a), 68 
— homolepis, 68, Fig. 12 (a), 69 
— koreana, Fig. 10 (a), 67 
— lasiocarpa, 68, 71 
arizonica, 68, 71 
— magnifica, 71 
— Mariesii, 67 
— nobilis , 68, 71 
— Nordmanniana, Fig. 10 (b) ,67,71 
Fig. 12 (b), 69 
— Pinsapo, 67 
'■ glauca, 67 
— procera, 68, 7 1 
j — glauca, 68, 71 
j — religiosa, 69 
I — sachalinensis, 70 
I — sibirica, 70 
| — spectabilis, 70 
| — Veitchii, 70 
— venusta, 69 
Albizzia julibrissin rosea, 2 7 
American Association of Botanical 
Gardens and Arboretums, 14 
Autikon Botanikon,” 8 
Azaleas, Ghent Hybrid Hardy in New 
England, 37-40 
Bailey, L. H., 50 
Beetles, Mexican Bean, 6 
— Striped Cucumber, 6 
Cabbage maggots, 3 
— worms, 6 
Case, James B., memorial, 8 
— , Miss Louisia W., 8 
Celastrus, 45 
Clematis collection, 2 4 
Cion, definition of, 10 
Crab apples, 23 
“Crab Apples for America,” 44, 56 
Crab Apples for Ornamental Fruit, 
41-44 
— , dates between which fruits are 
colorful and effective, 42-43 
Cutworms, 3 
“Edible Wild Plants of Eastern North 
America,” 44 
Ellery, Mrs. William, 40 
Evergreens, Broad-leaved in good con- 
dition, 21—22 
— , Broad-leaved injured, 22 
— , Narrow-leaved, 17 
— , Winter Foliage Color of, 17-20 
Fernald, M. L., 44 
Firs, Simple Key to the, 65 
Fir, twig, Fig. 8 (a), 66 
— , terminal bud, Fig. 9 (a), 66 
Form, definition of, 9 
[ 78 ] 

Fruits, Yellow or White Growing in 
the Arnold Arboretum, 45-48 
— , remaining March 26, 1943, 14-15 
— , Sources where they may be ob- 
tained, 48 
— , White, 46, 48 
— , Yellow, 45—48 
Hardiness Map, 53 
Hemlock, needle of, Fig. 1 (a), 58 
Hemlocks and Spruces, Simple Foli- 
age Key to the, 57-64 
Hybrids, Naming, 12 
Juniperus horizontalis plumosa, 17 
Key to the Firs, 65 
— to the Hemlocks and Spruces, 
57~64 
— to the Pines, 49—56 
Kinsey, A. C. , 44 
Lilacs, 23 
Malus Halliana Parkmannii, 23 
— Zumi calocarpa, 23 
Name, Publishing the horticultural, 12 
— , Rules for selecting the horticultu- 
ral, 1 1 
— , Selecting the new horticultural, 1 0 
Naming of Horticultural Varieties, 
The, 9-13 
Pests, Vegetable, 3 
Picea, 58 
Abies, 37, Fig. 4 (b), 60, 61, 64 
vars., 64 
— asperata, 61 
bicolor, 63 
— Breweriana 62, 63 
Engelmanni, Fig. 5, 61, 62 
— glauca, 61, Fig. 6, 62, 63, Fig. 7, 
64 
— — albertiana, 63 
conica, 60 
— — densata, 63 
— Glehnii, 63 
— jezoensis, 62 
— koyamai, 64 
— mariana, 60, 62 
Doumetii, 60 
obovata, Fig. 7, 64 
Omorika, Fig. 6, 62 
— orientalis, 63 
aurea, 64 
polita. Fig. 4 (a), 60, 64 
— pungens, Fig. 3, 60, 61 
argentea, 60 
Bakeri, 62 
glauca, 60 
Kosteriana, 62 
Moerheimii, 60 
— purpurea, 62 
— rubens, 64 
— Schrenkiana, 63 
— sitchensis, 62, 63 
— Smithiana, 63 
— Wilsonii, 61 
Pines, Simple Key to the, 49-56 
Pinus, 50 
— albicaulis, 5 1 
— aristata, 50 
— attenuata, 52 
— Ayacahuite, 52 
— Banksiana, 55 
— Bungeana, 52 
— - canariensis, 54 
— caribaea, 54 
— Cembra, 51 
sibirica, 51 
— cembroides, 54 
— Parryana, 52 
— Coulteri, 52, 54 
— densiflora, 55, 56 
— - — oculus-draconis, 54 
umbraculifera, 55 
— echinata, 54, 56 
— flexilis, 51 
tw] 

Pinus koraiensis, 51 
— Lambertiana, 51 
— monticola, 51, 52 
— Mugo, 55 
compacta, 55 
— pumilio, 55 
— nigra austriaca, 55 
Poiretiana, 55 
— palustris, 54 
— parviflora, 51 
glauca, 51 
— Peuce, 51 
I — Pinaster, 56 
— ponderosa, 52 
scopulorum, 54 
— pumila, 51 
— pungens, 55 
— radiata, 52 
— resinosa, 55 
f— rigida, 52 
— Sabiniana, 54 
— Strobus, 51 
fastigiata, 51 
nana, 51 
— sylvestris, 55 
aurea, 55 
rigensis, 55 
* Watereri, 55 
- — tabulaeformis, 54, 55, 56 
f— Taeda, 52 
— Thunbergii, 55, 56 
— Torreyana, 52 
— virginiana, 55 
Potato blight, 7 
— bugs, 7 
Pseudotsuga, 66 
— taxifolia, 66 
glauca, 66 
, Terminal bud, Fig. 9 (b), 66 
Rafinesque, C. S., 8 
Rhododendron arborescens, 37-39 
- “Aurore de Royghem,” 38 
— “Beaute Celeste,” 38 
~ ealendulaceum, 37, 38 
— “Cardinal,” 38 
— “Comte de Flandre,” 38 
— ‘ Flamboyant,” 38 
— “Fiirst Camille von Rohan,” 38 
- gandavense, 37-40 
— “General Trauff, ” 38 
— “Gloria Mundi,” 38 
— “Heureuse Surprise,” 38 
— Josephine Klinger,” 38 
— 'Julius Caesar,” 38 
— luteum, 37, 40 
— “Minerva,” 38 
— molle, 37, 38, 40 
— mucronulatum, 37, 40 
— nudiflorum, 37, 38 
— obtusum japonicum, 37, 38 
Kaempferi, 37, 38, 40 
— “Pallas,” 38 
— “Pucelle,” 38 
— roseum, 37 
— Schlippenbachii, 37, 38, 40 
— Vaseyi, 37 
— viscosum, 37, 38 
Shrub collection, 24 
Spruce, Needle of, Fig. 1 (b), 58 
— , Twig, Fig. 8 (b), 66 
Spruces, Simple Foliage Key to Hem- 
locks and, 57-64 
Squash vine borers, 7 
Striped cucumber beetles, 6 
Sty rax Obassia, 27 
“Sylva Telluriana,” 8 
Temperatures, minimum, 25-26 
Thuja occidentalis, 17 
Tsuga, 58 
— canadensis, Fig. 2 (a), (c), 58, 59 
— caroliniana, 59 
— diversifolia, 58 
[ 7 »] 

Tsuga heterophylla, 59 
— Mertensiana, 59 
Sieboldii, Fig. 2 (b), 58 
Variety, definition of, 9 
Vasseur, Louis, 24 
Vegetables, Planting, 1-8 
— , Planting dates, 2 
— Planting information, 4-5 
Winter Injury, to flower buds only 
during winter 1942-43, 34 
— , Hardiness Map, 53 
— in the Arnold Arboretum during 
winter 1942-43, 25-26 
— , plants killed to ground during 
winter 1942-43, 28-30 
— , plants partially injured during 
winter 1942-43, 30-34 
— , plants uninjured during winter 
1942-43, 35-36 
These bulletins will be discontinued until Spring of next year. 
Subscription renewals for 1944 are now due. Send the subscription price of 
$1.00 to Arnoldia, Arnold Arboretum, Jamaica Plain, Massachusetts, at your 
early convenience.